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International Review on Modelling and Simulations Vol. 4 N. 6---- Part A
International Review on Modelling and Simulations Vol. 4 N. 6---- Part B
International Review on Modelling and Simulations Vol. 4 N. 6---- Part C
International Review on Modelling and Simulations (Vol.
4 N. 6) - December 2011 - Papers (Part A)
International Review on Modelling and Simulations (Vol.
4 N. 6) -
December 2011 - Papers (Part B)
International Review on Modelling and Simulations (Vol.
4 N. 6) -
December 2011 - Papers (Part C)
International Review on Modelling and Simulations - Papers (Part A)
Evaluation of Capacitance Requirements for Constant Voltage Operation of a
Self-Excited Induction Generator in Stand Alone Mode
by K. Subramanian,
K. K. Ray
Vol. 4. n. 6, pp. 2749-2755
Abstract - In this
paper, the authors proposed a simple technique to inject capacitors to
regulate the terminal voltage of Self-Excited Induction Generator (SEIG)
operating as a stand-alone mode. It is well-established theory that a
minimum leading VAr (reactive volt-ampere) requires to meet the
excitation of an SEIG when operating as a stand-alone mode. A simple
model is proposed to realize the theory. Analysis of the steady state
model shows that, as the load lagging reactive power increases a leading
VAr is required to inject over and above the minimum capacitance to
regulate the load terminal voltage. A simple soft switch technique is
adopted to inject the capacitor to provide the necessary leading VAr.
Experimental results and Mat lab simulation results shows the validity
of the proposed system. Analysis of the result also presented.
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Keywords: Self-Excited Induction Generator, Capacitorse, Steadystate Analysis, Simulation, Soft Switching.
A Case for the Establishment of Malaysian Standard for Biodegradable Insulation
Oil in Malaysia Transformers
by Abubakar A.
Suleiman, Nor Asiah Muhamad
Vol. 4. n. 6, pp. 2756-2763
Abstract - – The
dielectric properties of insulation oil in power transformers are
dependent on the chemical structure of the oil. Although mineral oil
based insulation oil is the common liquid dielectric used in power
transformers, environmental and safety issues are pressurizing many
stakeholders from developed countries to consider alternative fluid as
transformer fluids. Vegetable (natural ester) based insulation oil is a
viable alternative that has been commercialized in some countries. This
paper presents results from the study done to ascertain the feasibility
of using commercially available biodegradable insulation oil (Envirotemp®
FR3™) for Malaysia power transformers. It was found that the tested oil
failed to meet some of the standard insulating property values as
stipulated in the Malaysian Standard (MS 2322:2010) and this was because
the MS 2322:2010 is the standard for “Fluid for electrotechnical
application-Unused mineral insulating oils for transformers and
switchgear” which cannot be applied to Vegetable based insulation oil.
This can lead to a misleading conclusion on the characteristics of
natural ester oil as a substitute to mineral oil in power transformers.
It is therefore pertinent to have a Malaysian standard property values
for vegetable oil (natural esters) guiding researcher, manufacturer and
users of “vegetable oil (natural ester) filled transformer in Malaysia”.
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Keywords: Mineral Oil, Biodegradable Oil, Insulation Oil, Malaysian Standard, Power Transformers.
Starting Dynamics of Smart Motor Controller-Fed Induction Motors with Parameter
Variation
by Nafeesa K, Saly
George
Vol. 4. n. 6, pp. 2764-2769
Abstract - Starting
performance analysis of smart motor controller-fed three phase induction
motor drives is presented in this paper. Identically rated machines with
different motor parameters are used for the work and establish the
concept of dependence of optimum firing angle on motor parameters. The
angle at which the negative torque pulsation is zero with minimum
acceleration time and other electrical characteristics having
satisfactory values is taken as the optimum firing angle. Effect of
variation of each motor parameter on the starting performance is also
investigated. Results shows that a suitable parameter combination
significantly improved the starting performance
of induction motors.
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Keywords: Induction Motor Starting, Optimum Firing Angle, Parameter Dependence, Smart Motor Controller.
About a
Possibility to Fuse Monitoring and Testing
by Adrian Plesca,
Monica Rotariu, Florin Daniel Irimia, Mihai Andrusca
Vol. 4. n. 6, pp. 2770-2779
Abstract - It
presents a new possibility concerning the monitoring of the electrical
equipment and installation, by using the information from the radiation
electromagnetic field. The results contain in this article is obtained
with the help of the numerical simulation in the EMTP software. It
compares the numerical results with testing characteristics,
experimentally determined for a high breaking capacity fuse.
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Keywords: Electrical Fuse, Data Acquisition, Monitoring, Magnetic Field, Testing.
Dynamic Analysis of Unbalanced Magnetic Pull in Squirrel Cage Induction Motors
by the Improved Winding Function Method
by Sadegh Shamlou,
Mojtaba Mirsalim
Vol. 4. n. 6, pp. 2780-2787
Abstract - Any kind
of electrical, mechanical and magnetic unbalances causes unbalanced magnetic
pull in electric machines. This paper presents the impacts of all kinds of
static, dynamic, and mixed eccentricities, rotor skew and loading effects on
unbalanced magnetic pull in three-phase squirrel cage induction machines by
means of improved winding function method. The method also considers the exact
function of air gap eccentricity, slot effects, magnetic intensity variation in
the air gap, and the exact mmf function over a slot pitch. The simulation
results show the high capabilities of the improved winding function method in
very fast (a few minutes in contrast to hours and days) and accurate analysis of
electric machines compared to the finite element method.
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Keywords: Eccentricity, Improved Winding Function Method, Unbalanced Magnetic Pull.
Effect of Phase Advancing in a Stand- Alone Switched Reluctance Generator
by M.Asgar,
E.Afjei, A.Siadatan
Vol. 4. n. 6, pp. 2788-2794
Abstract - The
switched reluctance motor is a singly excited, doubly salient machine
which can be used in generation mode by selecting the proper firing
angles of the phases. Due to its robustness, it has the potential and
the ability to become one the generators to be used in harsh
environment. This paper briefly discusses energy conversion by a
switched reluctance generator (SRG) when two switch per phase converter
circuit and discrete position sensors are employed. It is well known
fact that, as the generator’s speed increases by a prime mover the shape
of current waveform changes in such a way that limits the production of
generating voltage. At high speeds, it is possible for the phase current
never reaches the desired value to produce enough back-EMF for
sufficient voltage generation, therefore, the output power falls off. In
order to remedy this problem, the phase turn on angle is advanced in a
way that the phase commutation begins sooner. Since one of the
advantages of this type of generator is its variable speed then, the
amount of advancing for the turn on angle should be accomplished
automatically to obtain the desired output voltage according to the
speed of the generator, meaning, as the generator speed increases so
should the turn on angle and vice versa. In this respect, this paper
introduces an electronic circuit in conjunction with time reshaping of
the command pulses obtained from position sensors and the drive
converter to achieve this task for a desired output voltage when a SRG
feeding a resistive load. To evaluate the generator performance, two
types of analysis, namely numerical technique and experimental studies
have been utilized on a 6 by 4, 30 V, SRG. In the numerical analysis,
due to highly non-linear nature of the motor, a three dimensional finite
element analysis is employed to calculate some of motor parameters and
then using these parameter current shape and magnitude is computed,
whereas in the experimental study, a proto-type generator and its
circuitries have been built and tested using two switch per phase
converter. A linear analysis of the current waveform for the generator
under different advancements of the turn on angle has been performed
numerically and experimentally and the results are presented.
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Keywords: SRG, Switched Reluctance Generator & Control, Phase Advancing and SRG.
Dynamic Performance of Wind Asynchronous Generators Using Different Types and
Locations of Fault
by R. Rabbani, A.
F. Zobaa
Vol. 4. n. 6, pp. 2795-2801
Abstract - The most
important factors restricting further utilisation of wind resources are
the fortuitousness of the natural resource and the particularity of the
technology used in wind power generation. In this paper, the dynamic
performance of wind farms with an asynchronous generator (i.e. squirrel
cage generator), are analysed in the case of various faults and
disturbances in the transmission system. The focus of this study is on
wind farms that are connected with transmission lines to the strong
power system. The impact of the integrated wind farms on the voltage,
reactive power, power flow and frequency at the connection point during
disturbances is simulated. Furthermore, the effect of dynamic
characteristics of the wind turbines on the grid transient voltage and
the power system frequency stability are investigated. Simulation
results for short circuit current contribution for different types of
faults and locations obtained through transient analysis using a
squirrel cage generator model are presented. Obtained waveforms are
analysed to explain these behaviors, such as peak values for voltage,
frequency, reactive power and short circuit current during disturbances
for single line to ground, double line to ground, line to line and three
phase faults.
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Keywords: Squirrel Cage Generator, Frequency Stability, Voltage Stability, Short Circuit Level.
Dynamic Performance of the Wind Synchronous Generators with Different Types of
Excitation Systems
by S.Khaleghi
Kerahroudi, A. F. Zobaa
Vol. 4. n. 6, pp. 2802-2810
Abstract - In recent
years there has been an increasing trend towards the use of wind power
generation, also the requirements for the connection of wind power
plants (WPPs) to the electrical grid has also significantly changed
according to system operator [1]. Wind power plants include very
different technologies such as synchronous and asynchronous generators.
This paper investigates dynamic performance of wind synchronous
generator using various types of exciter such as AC, Static and Solid
state exciter. In addition the impact of various types of excitation
system on short circuit current and transient voltage and frequency
stability are studied.
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Keywords: Synchronous Generator, Excitation Systems, Stability, Short Circuit Currents.
Comparison between a Conventional and an Intelligent Direct Torque Control
Strategy
by Hamid. Chaikhy,
Mohamed. Khafallah, Abd Ellah. Saad Khalid Chikh And Mouna. Es-Saadi
Vol. 4. n. 6, pp. 2811-2816
Abstract - this
paper presents a contribution for detailed comparison between fuzzy
direct torque control (FDTC) strategy of Induction Machine (IM) using
FLC and fuzzy logic switchers (FLS), and the conventional DTC using the
two PI and IP controller. The performances of those two control schemes
are evaluated and compared by simulation in terms of speed, flux,
torque, current ripples and transient responses.
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Keywords: Direct Torque Control, PI-Controller, IP-Controller, Fuzzy Logic Controller, Switching Table, Fuzzy Logic Switcher Induction Machine.
A New Approach of Minimizing Torque Ripple for Brushless DC Motor Using Current
Controlled Space Vector Modulation Based Control Scheme
by
V.Viswanathan, S.Jeevananthan
Vol. 4. n. 6, pp. 2817-2825
Abstract - This
paper describes a novel Current Controlled Space Vector Pulse Width
Modulation (CCSVPWM) technique to minimize the torque ripples in BLDC
motor. The current ripple, created due to the stator winding inductance
and deviation of back emf, leads to generation of ripple in the torque
and prevents the usage of BLDC motor in a precise servo drive system.
This technique can also serve to reduce the torque ripple because of
current commutation. The paper includes MATLAB/SIMULINK results of
conventional, unipolar, bipolar current control algorithms (CCAs),
varying input voltage method (VIVM) and a new CCSVPWM approach. The
comparison of simulation results show that the current waveforms of the
current controlled SVPWM are smoother and the output torque exhibits
lower ripple contents. This control method improves the system
performance with low torque ripple.
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Keywords: BLDC Motor, Current Controlled SVPWM Technique, Torque Ripple.
Direct Torque Control of Induction Motor Drive Using a New Pattern of Four
Switch Three Phase Inverter
by Seyed Jafar
Salehi
Vol. 4. n. 6, pp. 2826-2833
Abstract - This
paper presents a novel control method for four switch three phase
inverter (FSTPI) and will implemented in the induction motor drive.
Look-up table in the new method will changed for improvement of various
condition of drive performance , so a suitable switching table has been
derived which selects the inverter switching states to fulfil the torque
and flux requirements. Moreover comparisons with direct torque control (DTC)
of induction motor fed by conventional FSTPI confirm that the new
topology can be alternative to the conventional topology for low power
low cost induction motor drive. Matlab simulink is used for simulation
results.
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Keywords:
Induction Motor Drive, Direct Torque Control, Four Switch
Inverter, Low Torque Ripple.
Modeling, Simulation and Torque Ripple Reduction of Three Phase Two Layers 6/4
Hybrid Switched Reluctance Motor/Filed-Assisted Generator
by A.Siadatan,
V.Najmi, E.Afjei
Vol. 4. n. 6, pp. 2834-2845
Abstract - In this
paper, a modeling and simulation analysis of two layers 6/4 three phase
Switched Reluctance (SR) Machine is carried out. This machine consists
of two magnetically dependent stator and rotor layers, where each stator
layer includes six salient poles with windings wrapped around them,
while the rotor comprises of four salient poles with different arc
lengths and no windings. There is a stationary reel, which has the field
coils wrapped around it and is placed between the two-stator sets. The
distinctive point of this machine is its ability to work in motor and
generator modes, which leads to hybrid operation. The mathematical model
is carried out to obtain the characteristics of this machine (motor and
generator). The torque ripple reduction is done as well by a novel
introduced method using Rotor Shifting Method (RST). Furthermore,
machine operations as SR motor and generator is simulated by 3D Finite
Element Method (FEM). Finally, the mathematical model and simulation
results are compared.
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Keywords: Switched Reluctance Motor, Switched Reluctance Generator, Finite Element Method, Curve Fitting, Rotor Shifting Method.
Study of Switching Frequency and Dead Time Effect by SVPWM Implementation in
FPGA Controller
by Davar
Ghalledar, Mehdi Samiei Sarkhanlo, Akbar Danandeh
Vol. 4. n. 6, pp. 2846-2850
Abstract - In this
paper effect of dead time and switching frequency on high frequency
harmonics has been investigated. The Space Vector PWM (SVPWM) technique
is designed and implemented for control three-phase voltage source
inverter by using a FPGA (Field Programmable Gate Array) controller. In
the power electronic sub circuit a voltage inverter is built of
different modules and A new kind OF FPGA controller EP1C12Q240C8 of
ALTERA is used in the control sub circuit. The dead time is necessary to
prevent the short circuit of the DC link in PWM voltage inverters. In
this case, delay between the pulse and reverse pulse to be changed and
the software has been created, so we can check influence this phenomenon
on the level of harmonic.
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Keywords: Dead Time, FPGA Controller, SVPWM, Switching Frequency, Voltage Inverter .
A
Comparison of High Performance Control Algorithms for Three-Phase Shunt Active
Power Filters
by W.
Lenwari, M. Odavic
Vol. 4. n. 6, pp. 2851-2857
Abstract - In this
paper, a three-phase shunt active power filter (SAPF) is introduced for
compensation of harmonic currents caused by non-linear loads in the
distributed power system. A SAPF is a power electronic device which has
been developed to improve power quality. The current control of shunt
power filters is critical since poor control can reinforce existing
harmonic problems. Various control strategies have been proposed by many
researchers. In this paper, a comparison evaluation of the performance
of three current control algorithms, proportional plus resonant (PR),
predictive based controller and iterative learning based controller, is
presented with an identical system specification. The design procedure
and principle of these current control methods are also presented in
details. Simulation results show the comparison of transient response,
steady state control and performance in the presence of variation of
supply impedance between these control techniques.
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Keywords: Shunt Active Power Filters, Proportional plus Resonant Controller, Predictive controller, Iterative Learning Controller, Power Quality.
Optimal
Fuzzy Logic Controller Design for Shunt Active Power Filters
by P.
Prasomsak, K-L. Areerak, K-N. Areerak
Vol. 4. n. 6, pp. 2858-2870
Abstract - The
optimal design of the fuzzy logic controller to control the compensating
current of the shunt active power filter is presented in the paper. The
artificial intelligence technique called the adaptive tabu search (ATS)
algorithm is used to design this controller to minimize the %THD of the
source current. The Mamdani max-min and the mean of maximum approaches
are used for the fuzzy inference and the defuzzification method,
respectively. In the paper, the aim of the optimal design using the ATS
algorithm is to design the input and output membership functions for the
fuzzy logic controller. Moreover, the performance improvement of the
instantaneous power theory to identify the harmonic currents of the
power system is presented in the paper. The fuzzy logic controller with
and without the ATS design are considered for the comparison of the
harmonic elimination performance. The simulation results show that the
fuzzy logic controller designed by the ATS algorithm can provide the
minimum %THD of the source currents after compensation. The %THD also
follows the IEEE Std.519-1992. In addition, the optimal design of the
fuzzy logic controller based on the ATS algorithm does not need the
engineering experience.
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Keywords: Adaptive Tabu Search, Fuzzy Logic Control, Shunt Active Power Filter, Instantaneous Power Theory.
Optimal
Design of Shunt Active Power Filters Using a Particle Swarm Optimization
by T.
Narongrit, K-L. Areerak, K-N. Areerak
Vol. 4. n. 6, pp. 2871-2878
Abstract - This
paper presents the application of a particle swarm optimization
algorithm to design the shunt active power filter controlled by
hysteresis current control. The objective of searching is to minimize %THD
of the source current. The results are compared with that designed from
Ingram and Round approach. The simulation results confirm that the
particle swarm optimization can provide the minimum %THD of the source
current compared with the Ingram and Round method. The %THD also follows
the IEEE std.519-1992.The design of the shunt active power filter based
on the particle swarm optimization algorithm is flexible and can improve
the performance of the filter.
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Keywords: Particle Swarm Optimization, Shunt Active Power Filter, Hysteresis Current Control.
High Voltage-Boosting Converter Using Coupled Inductor and Charge Pump with
Active Voltage Clamping
by K. I. Hwu, Y.
T. Yau
Vol. 4. n. 6, pp. 2879-2886
Abstract - A high
voltage-boosting converter is proposed herein, which combines one
coupled inductor and one charge pump. Under a low input voltage with a
high input current, the proposed converter has high voltage conversion
ratio, and possesses an active voltage clamping circuit which pumps some
portion of the leakage inductance energy to the output so as to increase
the efficiency at light load, thereby causing the efficiency at light
load to be very high. Hence, it is very suitable for the burn-in test of
the buck-type converter. In this paper, the basic operating principles
of the proposed converter are provided, together with some experimental
results to verify its feasibility and effectiveness.
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Keywords: Active Voltage Clamping, Coupled Inductor, Charge Pump, Voltage-Boosting Converter, Voltage Conversion Ratio.
by Rosnazri Ali, Ismail Daut, Soib Taib, Noor Shahida Jamoshid
Vol. 4. n. 6, pp.
2887-2893
Abstract - This
paper presents a special designed power switching function generator
that produces 4 types of waveforms; square-wave, sinusoidal PWM, quasi-sinewave
or multilevel and high-frequency DC pulses with a total of 14 different
distinctive characteristics. The generator is exceptionally a useful
tool to complement the students and researchers in power electronics
areas which supports in their learning and design process. The generator
is capable of producing selected waveforms which can deliver a 30W
maximum power into a particular load. It is highly useful in harmonics
analysis of inverters, true RMS measurements, switching devices driving
signals, high-frequency switching transformer designs and filtering
components for selective harmonics elimination.
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Keywords: Power Switching Generator; Harmonics Analysis; Driver Signals; High-Frequency Switching Transformer Designs.
A New Approach to Eliminate Undesired Harmonics of a Single-Phase Square-Wave
Inverter Using a Transformer
by N. Ghardash
Khani
Vol. 4. n. 6, pp. 2894-2900
Abstract - This
article proposes a new method to eliminate undesired harmonics in the
output of a single-phase square-wave inverter. The method has some
important advantages that outweigh square-wave inverters and similar
types. Besides being easy to control and construct, it has a high
efficiency due to its low-frequency switching pattern. It would also be
very useful in high-power demands, and capable of driving huge motors
used in heavy industries. In this paper, the Matlab/Simulink simulation
results of the whole system by the proposed method are presented and
compared with experimental results of a prototype to verify its
advantages over existing methods.
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Keywords: Square-Wave Inverter, Driver, MOSFET, Transformer, Gate Pulse, Total Harmonic Distortion, Uninterruptible Power Supplies, SPWM (Sinusoidal Pulse Width Modulation), SVPWM (Space Vector PWM), IGBT (Insulated Gate Bipolar Transistor).
Mitigation of Subsynchronous Resonance by Subsynchronous Current Injection with
STATCOM
by M. Janaki, R.
Thirumalaivasan, Nagesh Prabhu
Vol. 4. n. 6, pp. 2901-2908
Abstract - A
suitable selection of hybrid compensation can improve the power transfer
capability and voltage regulation of long transmission systems. In this
paper, hybrid compensation is realized by a combination of fixed series
capacitor and shunt active FACTS controller STATic Synchronous
COMpensator (STATCOM). The objective is to investigate the
subsynchronous resonance characteristics of the hybrid compensated power
system and propose a simple method for the extraction of subsynchronous
component of line current using filter. The extracted subsynchronous
frequency component is injected by the STATCOM at PCC, prevents the flow
of subsynchronous current through the generator, and increases the
damping of the system at critical torsional frequencies. This novel
technique is termed as Subsynchronous Current Injection. The design of
Subsynchronous Current Injector is based on damping torque analysis and
Genetic Algorithm. The study system is adapted from IEEE First Benchmark
model. The results show the effectiveness of the proposed Subsynchronous
Current Injector in damping SSR. The SSR characteristics are analyzed
based on linear analysis methods and nonlinear transient simulation.
Linear analysis includes, Damping torque and eigenvalue analysis, which
uses D-Q model of the system. The results of linear analysis are
verified by performing transient simulation with detailed nonlinear
model of the system.
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Keywords: Subsynchronous Resonance (SSR), Torsional Interaction (TI), Damping torque, Eigenvalue, FACTS, Voltage Source Converter (VSC), Static Synchronous Compensator (STATCOM), Genetic Algorithm (GA).
Islanding Detection Method for VSI Based Distributed Generation by Considering
its Switching Frequency
by Umashankar S.,
Kothari D. P., Vijayakumar D.
Vol. 4. n. 6, pp. 2909-2918
Abstract -
Distributed or dispersed generation (DG) is widely used all over the
world in order to avoid the transmission and distribution (T&D) line
losses, to improve power quality, and to improve the voltage profile of
the system etc. Unintentional Islanding is one of the major issues with
DG. Current practice is that almost all utilities require DG to be
disconnected from the grid with a maximum delay of 2 seconds of
unintentional islanding (IEEE 1547 – 2003 standard). Islanding Detection
methods can be broadly classified as Active, Passive and Hybrid methods,
each having its own merits and demerits. Active detection method is safe
reliable but very costly. Passive methods are comparatively cheap but
they have a very large Non Detection Zone (NDZ). Hybrid detection
methods have prolonged detection time as they use both the active and
passive methods. This paper proposes one of the finest solutions to one
of the above problems, achieving zero NDZ with a Passive islanding
detection technique, considering the switching frequency of an inverter
in the DG system. This also satisfies the IEEE (2 seconds) standard.
Islanding is a phenomenon, which occurs when a section of the utility
system containing a Distributed Generation (DG) is isolated from the
main utility voltage source, but the local generation continues to
deliver power to the local loads. Unintentional islanding may pose
safety hazards as well as equipment damage at both the customer and the
utility sides. This paper presents the modelling and development of the
Phase Jump Detection (PJD) based passive Anti-Islanding scheme for the
grid connected photovoltaic (PV) inverter. A closed loop control system
utilizing the vector control and the SVPWM technique for the PV inverter
with PJD scheme has been simulated in MATLAB/Simulink environment. The
model has also been tested for various grid conditions with varying
switching loads. The clear description of the model has been given and
the results are then presented.
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Keywords: Distributed Generation (DG), Islanding Detection, Phase Jump Detection, SVPWM Inverter, Anti Islanding.
A New Power Factor Correction Approach for Cost and Energy Saving in Industrial
Motor Drives
by D.Prince
Winston, M. Saravanan, S.Arockia Edwin Xavier
Vol. 4. n. 6, pp. 2919-2925
Abstract - Nowadays,
Energy and cost saving are very important factors for industries. In
industries, nearly 75% of the total load comprises motors. Motors may be
dc or ac motors. Due to low price, less maintenance, robustness, and
reliability, ac induction motors are used in most of the industrial
applications. Induction motors have power factor problem. This paper
gives the clear understanding of power factor for the beginners of this
field. This paper describes the different power factor correction
methods used in industries and also provides a new power factor
correction approach for cost and energy saving in industry. The proposed
method is verified by simulation using MATLAB-SIMULINK for a three phase
5.4 Hp and 150Hp squirrel cage induction motors. The practical work is
done for 5Hp three phase squirrel cage induction motor. The results for
both simulation and practical are discussed in this paper.
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Keywords:
Power Factor Correction, Loss Reduction, APFC, SCBAPFC,
Power Converters, Industrial Thumb Rule, Three Phase Induction Motor.
Modeling and Simulation of DSTATCOM using Space Vector Pulse Width Modulation
for Load Variation
by K.Murugesan,
Ranganath Muthu
Vol. 4. n. 6, pp. 2926-2935
Abstract - Power
system generators supply the required active power and part of the
reactive power. Insufficient reactive power in the power system affects
the bus voltage and the sensitive loads connected to it. To keep the bus
voltage as per the grid code requirement, required reactive power should
be supplied and excessive reactive power should be absorbed. Capacitor
banks and reactor banks were acting as source and sink of reactive power
respectively. Self-controlled thyristor switched capacitors and
thyristor controlled reactors were also doing the same with improved
performance. This kind of compensation at the load side with improved
transient and dynamic stabilities is achieved by Distributed Static
Synchronous Compensator or DSTATCOM. This paper focuses on modeling of
Voltage Source Converters (VSCs) based DSTATCOM and its voltage
regulation performance for load variations. Cascaded vector controller
with Sinusoidal PWM (SPWM) and Space Vector PWM (SVPWM) switching
algorithms have been studied in the MATLAB-Simulink environment. It is
found that the SVPWM switching algorithm has reduced commutation losses,
lower harmonic content and better amplitude modulation index compared to
the SPWM switching technique.
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Keywords: Cascaded Vector Control, Sinusoidal PWM, Space Vector PWM, Voltage Source Converter, Voltage Regulation.
Artificial Neural Network Based Three Phase Shunt Active Filter for Line Harmonic
Elimination
by
N.Senthilnathan, T.Manigandan
Vol. 4. n. 6, pp. 2936-2943
Abstract - Power
quality is the ability of the electrical utilities to provide electrical
power without interruption. The growth in the use of non-linear loads
has caused power quality problems like high current harmonics and low
power factor. Several control algorithms, which are usually used to
resolve harmonic problems and their limitations, are discussed. This
paper presents a new and simple control strategy to determine reference
compensation currents, under balanced and unbalanced source voltages
which uses the Voltage Source Inverter (VSI) for harmonic filtering of a
three phase shunt active filter. Recently Neural Network (NN) based
Shunt Active Filter (SAF) gains attention and in this paper a new
control algorithm for NN based SAF is proposed. A three-phase six-pulse
converter with resistive load is considered as the non-linear load and
the switching pulse generation is based on carrier-less hysteresis based
current control.The design concept of the SAF using the proposed NN
based control algorithm is verified through simulation and the results
proved the effectiveness of the proposed algorithm in reducing the
overall percentage of total harmonic distortion (THD) and improving the
power factor for non linear loads.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Artificial Neural Networks, Shunt Active Filter, Voltage Source Inverter, Power Quality, Total Harmonic Distortion.
A Refined Space Vector PWM Signal Generation for Ten-Level Inverter
by G.Sambasiva
Rao, K.Chandra Sekhar
Vol. 4. n. 6, pp. 2944-2953
Abstract - A refined
space vector modulation scheme for a ten-level inverter system for
dual-fed induction motor drive, using only the instantaneous sampled
reference signals is presented in this paper. The dual-fed structure is
realized by opening the neutral-point of the conventional squirrel cage
induction motor. The ten-level inversion is obtained by feeding the
dual-fed induction motor with asymmetrical four-level inverter from one
end and symmetrical three-level inverter from other end. The proposed
space vector pulse width modulation technique does not require the
sector information and look-up tables to select the appropriate
switching vectors. The inverter leg switching times are directly
obtained from the instantaneous sampled reference signal amplitudes and
centers the switching times for the middle space vectors in a sampling
time interval, as in the case of conventional space vector pulse width
modulation.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Dual-Fed Induction Motor, Middle Space Vectors, Sinusoidal Reference Signals, Space Vector PWM, Ten-Level Inverter.
Constant Pulse Width Switching Strategy for Matrix Converter
by M.Senthil
Kumaran, R.Siddharth, M.Stalin, A.Divakhar, Ranganath Muthu
Vol. 4. n. 6, pp. 2954-2960
Abstract - This
paper explores a new constant pulse width switching (CPWS) strategy for
Matrix converter utilizing all valid switching vectors. The method
distributes voltage vectors with respect to minimum computed error. The
important features of the technique include superior over modulation
performance, inherent mitigating effect of unbalance at the input and
constant pulse width switching (CPWS) leading to lower switching
stresses. In this paper, under distorted input voltage conditions,
behavior of the Matrix converter controlled by CPWS is analyzed. This
proposed PWM algorithm is verified by MATLAB Simulation and hardware
experimentation on laboratory prototype.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Matrix Converter, Unbalanced Input, Over-Modulation Index, Error Compensation.
Simulation Model of
A Hybrid Energy System
by Ahmed R. Abul'Wafa,
A.T.M. Taha
Vol. 4. n. 6, pp.
2961-2966
Abstract - A hybrid
energy system (HPS) simulation model is developed to maximize the
renewable energy extraction at Farafra, an oasis in Egypt. In Farafra a
microgrid composed of 2*1.6 MW+1*2MW+2*2.5MW diesel generating units
(DG) is already installed and serve an electric demand consisting of
52365 KWh/day. The system may need to be upgraded. In the model, part of
the load is recommended to be supplied as deferrable load. Also battery/convertor
modules are added in the HPS so that when renewable power generation
exceeds local demand, energy can be stored and used during times when
renewable power is not available or the electrical load increases. The
model is based on two types of renewable power generation: wind turbine
generator and photovoltaic generator in conjunction with existing diesel
generators supply sources. The HOMER software was used to select an
optimum hybrid energy system sized according to the electric demand, the
availability of renewable energy resources and to maximize the renewable
energy to total energy ratio. The optimization process simulates every
system configuration in the search space and the feasible ones are
sorted by total net present cost (NPC). Sensitivity analysis shows that
the most least cost and optimized hybrid system is combination of 231
Enercon (330 kW) WTG; 155 Surrette 4KS25P batteries; and a 283 kW
Convertor requiring only 3916 hours annual operation of one of the 1.6
MW diesel generators and 2306 hours annual operation of the 2.0 MW
diesel generator. The two 2.5 MW diesel generators are saved. The
photovoltaic array was not chosen because its costs were not justified
with this particular solar regime and diesel cost.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Optimization Design, HOMER, Wind/PV Energy Hybrid System.
Insulated-Gate Bipolar Transistor Controlled Reactor
by Abdulkareem
Mokif Obais, Jagadeesh Pasupuleti
Vol. 4. n. 6, pp. 2967-2972
Abstract - In this
paper a controlled reactor using insulated-gate bipolar transistor (IGBT)
is presented. Controlled reactors are usually implemented by using
thyristors since the mid-1970’s and they are usually referred to as
thyristor-controlled reactors. A thyristor-controlled reactor (TCR) is
simply two anti-parallel thyristors connected in series with a fixed
inductor or reactor. In TCR, it is only required to specify the instants
at which its thyristors must start conduction. Once a thyristor
conducts, its current keeps on flowing as long as its magnitude is above
holding limit and hence no trigger is required after starting of
conduction. In addition, a thyristor will be naturally commutated as
soon as its current decays below holding limit. For IGBT, the instant at
which the device must start conduction and the conduction period must be
both identified because maintaining conduction requires keeping on
activating the device gate as long its current is still greater than
zero. The problem is how long should the IGBT conduct and when it will
be turned off? In this paper a reliable control strategy is adopted for
presenting the IGBT as a good replacement of thyristor in controlled
reactors. A demonstrating system is designed and implemented on the
computer program PSpice.
Copyright © 2011 Praise Worthy Prize S.r.l. -
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Keywords: Controlled Reactor, Power Quality, Reactive Power Control, Static VAR, TCR.
On the Sliding Mode Control of Saturated Systems Subjected to Norm Bounded
Uncertainty
by Borhen
Torchani, Anis Sellami, Germain Garcia
Vol. 4. n. 6, pp. 2973-2984
Abstract - This
paper deals with robust control of saturated systems. It presents a
design methodology of sliding mode control of a class of linear systems
with the presence of both constraint of saturation and norm bounded
uncertainty. In a first step, the design of the sliding surface is
formulated as a problem of root clustering of reduced uncertain system,
what leads to the development of a continuous and non-linear control
law. In a second step, a robustness analysis is performed. As result, an
approximation of the trajectory deviation of the uncertain system
compared to the ideal behavior is proposed. Finally, a numerical
application to double mass-spring-shock absorbers with one actuator is
illustrated to validate the theoretical results of this work.
Copyright © 2011 Praise Worthy Prize S.r.l. -
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Keywords: Sliding Mode Control, Norm Bounded Uncertainty, Saturation, Robustness.
An Accurate Multi-Train Simulation Tool for Energy Recovery Evaluation in DC
Rail Networks
by R. Barrero, O.
Hegazy, P. Lataire, T. Coosemans, J. Van Mierlo
Vol. 4. n. 6, pp. 2985-3003
Abstract - This
article presents a multi-train simulation tool based on quasi-static
averaged models of vehicles and a dynamic model of the DC network. It
models the interactions and energy exchange among vehicles running on
the line and shows the influence of the traffic density on the vehicles
energy regeneration and substations energy consumption.The tool can
simulate both conventional and modern rail networks equipped with
different energy saving technologies such as on-board and wayside energy
storage systems, hybrid trains and reversible substations. Thanks to the
detailed models, the tool can be used to both study any conventional
rail DC network and to design and predict the best solution in terms of
energy recovery for a particular network.The models of the complete
system have been validated with measurements taken on metro vehicles
running in regular service under different traffic conditions.
Simulation results show a good match between measurements and
simulations.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Multi-Train Simulation, Energy Recovery, Reversible Substation, Energy Storage.
International Review on Modelling and Simulations - Papers (Part B)
Rule-Based Expert System for PQ Disturbance Classification Using S-Transform and
Support Vector Machines
by M. A. Hannan,
Tea Chiang Wei, Alex Wenda
Vol. 4. n. 6, pp. 3004-3011
Abstract - This
paper presents a rule-based expert system for automatic identification
and classification of PQ disturbances by combining the improved
S-transform and SVM. The combined tools are used to integrate the
computation process and extracted features to formulate rules for
classification of the PQ disturbances.Rule formulataion is developed by
comparing standard deviation value of a disturbance signal that is
obtained from the S-transform analysis. SVM technique is used for data
classification and regression for training and testing the class level
and control feature parameters, respectively.Thus, based on the
distinctive features through SVM, the S-Transform formulated appropriate
rules and features contour that can easily be classify the PQ
disturbances.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Rule-Based Expert System, PQ Disturbances, Classification, S-Transform, SVM.
Smart AC-DC Power System with Voltage Fluctuation Control and Fault Analysis
by A. Thamilmaran,
P. Vijayapriya, R. Suresh, Dr. D. P. Kothari
Vol. 4. n. 6, pp. 3012-3018
Abstract - Due to
continuous exploitation of oil and gas reserves combined with the effect
of global warming has brought renewed interest in alternative energy
sources. Renewable power resources are safe, clean, and abundant in
nature. Recent research and development in renewable power generation
techniques such as photovoltaic, wind has shown excellent potential
towards building a sustainable energy economy in the next decade. The
energy sources and connecters need to be integrated to meet sustained
load demand while considering the natural whether conditions. The paper
focuses on the combination of wind and photovoltaic system to ensure
that system performs under all conditions. The system consists of a wind
generator and alternate energy conversion systems such as PV cells.
However, due to the power fluctuation of renewable energy sources,
voltage and frequency deviations are occurred in island power systems
whose ability to maintain stable supply–demand balance is low.
Therefore, it is necessary to control the system frequency and voltage.
From this viewpoint, a smart grid, which maintains stable supply–demand
balance is necessary. The proposed system has advantages of both dc and
ac grids. Output from the wind, PV cell and battery are maintained at
same voltage and connected to the common DC bus while the conventional
power supply modeled as three phase voltage source and several
controllable loads of different capacities are connected to the AC bus.
The system is analyzed under fault conditions. The Model is developed
using MATLAB- Simulink.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Wind Generator, PV Cell, Hybrid System, DC Grid, Controllable Loads.
Design and Implementation of a PLC Based Monitoring and Control System for
Reactive Power Compensation System
by Ramazan
Bayindir, Orhan Kaplan, Lokman Baran
Vol. 4. n. 6, pp. 3019-3028
Abstract - In this
study, a reactive power compensation system has been implemented using a
programmable logic controller (PLC). The four induction motors, which
are used as reactive power consumers, are run or stopped by PLC in the
power system. Thus the power system containing more than one reactive
power consumer has been prepared. The current and the voltage of the
power system are measured and then processed in the PLC to calculate the
power factor of the system. The power factor calculation procedure is a
novel algorithm developed by the authors. The required reactive power is
provided by switching the capacitor groups automatically using the
developed software. In addition, the developed system can protect the
induction motors against some possible problems, such as overcurrent,
high/low voltage, and phase sequence error. Owing to the improved
computer interface, starting and stopping of the motors and monitoring
of the parameters of the power system could be easily achieved using the
computer. Furthermore, it has been shown that the proposed system is
very flexible and expandable for different applications. In the study
the most important disadvantage is that the grid current waveform is
destroyed after reactive power compensation since the motors used as
load do not draw a complete sinusoidal current from the grid.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Power Factor, Reactive Power Compensation Capacitors, PLC.
The Roles of Static VAr Compensators in Smart Grids: a General Theory using
Power Analysis
by Félix R.
Quintela, Roberto C. Redondo, Norberto R. Melchor, Juan M. G. Arévalo
Vol. 4. n. 6, pp. 3029-3036
Abstract - Static
VAr Compensators (SVCs) owe their name to their ability to compensate
reactive power, but they can also perform other useful functions on
smart grids in order to improve the electric power supply. This paper
shows a general SVC theory based on the power analysis, which leads to a
system of linear equations that completely dictates the behaviors of
SVCs. This equation system can be used to deduce all the roles a SVC can
play in electrical systems, and to determine its reactance values for
each of those roles. As an example, the design values of SVCs are
obtained for some of these applications. Experimental tests are also
included.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Smart Grid, Three-Phase Load Balance, SVC, Power and Energy Losses, Phase-To-Phase Load.
An Enhanced Control Strategy for SSFCL in Limiting Fault Current in the
Distribution System
by M A Hannan
Vol. 4. n. 6, pp. 3037-3043
Abstract - This
paper deals with the modeling and simulations of solid-state fault
current limiter (SSFCL) for providing credible solutions to power
quality problems. An enhanced control strategy has been developed for
instantaneous detection of overcurrent and limitation of the fault
currents in the distribution system. The modeling of these devices is
based on graphic models using the electromagnetic transient simulation
program PSCAD/EMTDC.An extensive investigation are made to evaluate the
performance of the SSFCL in limiting fault currents for a system with
induction motor load and its capability in compensating voltage sags and
effect of changing FCL parameters. It was observed that the impact of
the induction motor load on the performance of the SSFCL proves that the
limiting fault currents are greater as compared to the system with
static loads. The current limiting reactor of the SSFCL plays an
important role in compensating voltage sags caused by the different
types of faults. Thus, the results of the SSFCL proved that it is a
suitable device for limiting fault current within 2 ms which is the
tolerable limit of the system. The developed models will be useful for
further power quality studies in a distribution system.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Control Strategy, SSFCL, Fault Current, Distribution System.
Static and Dynamic Stability Analysis of Distributed Energy Resources Components
with Storage Devices and Loads for Smart Grids
by L. Mihet-Popa,
V. Groza
Vol. 4. n. 6, pp. 3044-3050
Abstract - The
distributed energy resources (DER) contains several technologies, such
as diesel engines, small wind turbines, photovoltaic inverters, etc. The
control of DER components with storage devices and (controllable) loads,
such as batteries, capacitors, dump loads, are central to the concept of
the Smart Grids (SGs). A SG can operate interconnected to the main
distribution grid or in islanded mode. This paper presents experimental
tests for static and dynamic stability analysis carried out in a
dedicated laboratory for research in distributed control and smart grid
with a high share of renewable energy production. Moreover to point out,
on a laboratory scale, the coupling between DR and storage and to
effectively compensate wind fluctuations a number of tests have been
done. In order to find out the parameters of various types of DER
components for dynamic simulation models a number of tests are required
under different operation modes and loads. The testing reporting here
includes three modes of operation: stand alone, parallel/hybrid and grid
connection.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Distributed Energy Resources, Smart-Grid, Static And Dynamic Stability Analysis.
Estimation of Nonsinusoidal Operating Conditions in Electric Networks on the
Basis of Measurements
by A.Z.Gamm,
L.I.Kovernikova
Vol. 4. n. 6, pp. 3051-3058
Abstract -
Consideration is given to an algorithm intended for calculation of
electric network nonsinusoidal operating conditions by the state
estimation method. The state estimation vector is formed by the
magnitudes and phases of harmonic voltages including fundamental
voltage. The new generation measurement devices (Phasor Measurement
Units) are proposed to synchronously measure operating parameters at
different points of electric network. The suggested algorithm was used
to create a program for calculations. The authors present the
calculation results based on the data obtained in the experiments on the
physical model of electric network.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Power Quality, Nonsinusoidal Condition, State Estimation Method.
Practical Voltage Sag Mitigation Techniques – a Key Success Factor for Smart
Grid Implementation in Provincial Electricity Authority
by S. Songsiri, S.
Sirisumrannukul
Vol. 4. n. 6, pp. 3059-3069
Abstract - This
paper presents a practical implementation to mitigate voltage sag problems in
Provincial Electricity Authority (PEA)’s distribution systems in the Smart Grid
environment. PEA is developing a smart grid road map for next 20 years and the
improvement of power quality is one of the main important issues in the roadmap.
To become a voltage sag-free system, three methods are proposed for PEA:
reduction of fault clearing time by revision of protection scheme, insertion of
neutral grounding resistance, and resonant grounding. The advantages and
disadvantages of these techniques are illustrated by a 115/22 kV substation with
two outgoing feeders. The study results from transient simulations with
different fault locations by ATP-EMTP reveal that these three techniques are
capable of mitigating voltage sags originated by a single-line-to-ground short
circuit. However, although reducing fault clearing time and installing a neutral
grounding resistance are cost-effective, the customers connected to the faulted
feeder downstream to the fault are still disconnected. To avoid sustained
interruption for which the outage cost is of concern while respecting the
acceptable criteria defined by the ITIC curve, the resonant grounding is
introduced based on the principle of compensation between capacitive current
generated by the stray shunt capacitance of feeder and inductive current
generated by a Peterson coil.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Voltage Sag Mitigation, Smart Grids, Distribution Systems, Power Quality.
Microgrid Sizing Along with Reliability Consideration Using Particle Swarm
Optimization
by
Arash Navaeefard, Roozbeh Kamali, S.M.Moghddas Tafreshi, Omid Babayi
Vol. 4. n. 6, pp. 3070-3078
Abstract - The major
application of the MicroGrid (MG) is in remote areas where utility lines
are uneconomical to install due to terrain, the right-of-way
difficulties or the environmental concerns. In this paper a novel
intelligent method is applied to the problem of sizing in a MG such that
demand of residential area is provided, and reliability index is
considered as a constraint. In this MG, power generators are
photovoltaic (PV) /wind turbine, and battery bank is used as an energy
storage system. PSO algorithm has been used to optimize the cost
function, and has been simulated in MATLAB for justification purpose.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Wind Turbine, Photovoltaic, Battery Bank, Microgrid, Optimal Sizing, Reliability.
Multi-objective Optimal Operation of Microgrid with an Efficient Stochastic
Algorithm Considering Uncertainty of Wind Power
by B. Khorramdel,
H. Khorramdel, H. Marzooghi
Vol. 4. n. 6, pp. 3079-3089
Abstract - Due to
the rapid growth of utilization of Distributed Generations (DGs) in
microgrids, their different aspects have been the concern of recent
research. In addition, the penetration of wind power is growing rapidly
in microgrids around the world and depends on the capacity of the wind
farms; it may participate in microgrids. In such a case, the volatile
nature of wind power affects the operation of microgrids in many
different aspects. Considering the impact of wind power volatility on
microgrid operation and existence of some Electronically Interfaced DGs
(EIDGs) in a microgrid, this paper proposes a new Optimal Power Flow (OPF)
algorithm which uses multiobjective nonlinear programming technique and
includes three stages. This algorithm determines the optimal control
variables of each EIDG, such as PQ, PV and a new model of DGs which is
named Q-sharing DGs in a microgrid to achieve the minimum power loss and
improving the Voltage Profile Index (VPI). Considering some probable
wind speeds, in the third stage the best control variables are acquired
to schedule of reactive power through using results of two previous
stages. The proposed algorithm is applied to IEEE 34-bus distribution
test system and numerical studies show satisfactory results.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Distributed Generations, Microgrid, Optimal Power Flow, Q-sharing DGs, Reactive Power Control, Stochastic Algorithm.
Improving Reactive Power Margin for Voltage Stability Enhancement Using FACTS
Devices
by K.
Chandrasekar, N. V. Ramana
Vol. 4. n. 6, pp. 3090-3097
Abstract - Reactive
Power Margin (RPM) is an indicator of power system Voltage Stability
(VS). With this perspective, this paper presents the application of
Differential Evolution (DE) algorithm for Reactive Power Margin (RPM)
improvement using FACTS devices. Conventionally, RPM is evaluated using
V-Q curve analysis which suffers from the drawback of conservative
results due to step increment in voltage. This drawback is eliminated in
this paper by utilizing DE to directly search the voltage value instead
of incrementing it for RPM assessment while finding the optimal location
and settings of FACTS devices for RPM improvement. Further to improve
computational efficacy, power flow is performed using Broyden Shamanski
method with Sherman Morrison formula (BSS) instead of a conventional
Newton Raphson (NR) power flow. Simulation tests are carried out on IEEE
14, 30, 57 and 118 bus test systems. Results indicate that the proposed
approach enhances RPM and improves the computational efficacy better
when compared to the conventional approach.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Differential Evolution, FACTS Devices, Reactive Power Margin, V – Q Curve, Voltage Stability.
Generation Reliability Assessment in Power Markets Using MCS and Neural Networks
by Hossein
Haroonabadi, Hassan Barati
Vol. 4. n. 6, pp. 3098-3103
Abstract -
Deregulation policy has caused some changes in the concepts of power
systems reliability assessment and enhancement. In this paper,
generation reliability comparison in three kinds of power markets is
considered: Perfect competition, Monopoly and Oligopoly power markets.
Because of power market and generators’ forced outages stochastic
behavior, Monte Carlo Simulation (MCS) is used for reliability
evaluation. Also, for creating a unique structure, a feed forward neural
network which has similar numerical results in comparison with MCS
results, is used for generation reliability evaluation. The proposed
method is assessed on IEEE-Reliability Test System with satisfactory
results. In all cases, generation reliability indices are evaluated with
different reserve margins and various load levels. It will be shown that
if price elasticity of demand increases, reliability will improve. Also,
comparison of perfect competition and monopoly power markets shows that
whatever market becomes more concentrated, reliability will improve. In
an oligopoly power market, if a company’s share in the market increases
or price elasticity decreases, the company can mark up the price more
than before.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Generation Reliability, Power Markets, Monte Carlo Simulation, Neural Networks.
Security Constrained Unit Commitment in Iran's Electricity Market
by M. S. Javadi,
A. Meskarbashi, R. Azami, Gh. Hematipour, A. Javadinasab
Vol. 4. n. 6, pp. 3104-3112
Abstract - This
paper surveys on Security Constrained Unit Commitment (SCUC) based on
Iran's Electricity Regulation (IER). Day-Ahead (DA) power market and
operation of the Iran's national grid is addressed considering the
market regulation and operation rules which is managed by Iran Grid
Management Company (IGMC) as Independent System Operator (ISO). National
grid dispatching control center and data exchanging between main
supervisory control and relevant Area Control Centers (AOC) are
described in this paper. The market and operating infrastructure of the
national grid is also expressed. Energy market clearing mechanism in
Iran electricity market is based on Pay-as-Bid (PAB) which imposes some
concerns for market operator and participants. The DA power market
clearing which implemented in energy market satisfied the real
constraints and feasibility of the algorithm is proved by the simulation
studied.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Iran's Electricity Market, Pay-as-Bid Mechanism, Security Constraint Unit Commitment.
Reconfiguration of Distribution Network with Dispersed Generations Based on Ant
Colony Algorithm
by M. J. Kasaei,
H. Norouzi
Vol. 4. n. 6, pp. 3113-3118
Abstract - This
paper presents one of applications of the Ant colony algorithm method
for the reconfiguration of distribution networks with dispersed
generation (DG) to reduce power losses and voltage profile improvement
.The configuration optimization problem of distribution networks is a
combination optimization with a large search space involved the
operational constraints of the distribution. Dispersed generation
sources such as fuel cells, solar cells, wind mills and micro gas
turbines can be strategically allocated in distribution networks for
reducing power losses, network reinforcement, improving network
efficiency and reliability. The performance of the proposed method was
investigated on two distribution networks consisting of 16 and 10 buses.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Distribution Network, Dispersed Generation, Reconfiguration, Loss Reduction, Ant Colony.
Line Stability Index for Steady State Stability Enhancement Using FACTS Device
by C. Subramani,
Subhransu Sekhar Dash, A. F. Zobaa, Vivek Kumar
Vol. 4. n. 6, pp. 3119-3124
Abstract -
Estimating the margin in the loadability of the power system is
essential in the real time voltage stability assessment. Voltage
stability is currently one of the most important research areas in the
field of electrical power system. The condition of voltage stability in
a power system can be known using Voltage Stability Indices (Lmn). The
loading margin is one of the most widely known and accepted Lmn. Voltage
Stability Indices can be useful for estimating the distance from the
current operating point to voltage collapse point. The indices can
either reveal the critical bus of a power system or the stability of
each line connected between two buses in an interconnected network or
evaluate the voltage stability margins of a system. Flexible Alternating
Current Transmission Systems (FACTS) devices have been proposed as an
effective solution for controlling power flow and regulating bus voltage
in electrical power systems, resulting in an increased transfer
capability, low system losses, and improved stability. However to what
extent the performance of FACTS devices can be brought out highly
depends upon the location and the parameters of these devices. Unified
Power Flow Controller (UPFC) is the most promising FACTS device for
power flow control. The performance of this index is presented and the
effectiveness of the analyzed methods is demonstrated through simulation
studies in IEEE 14 bus reliability test systems.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Loading Margin, Voltage Stability Assessment, Contingency Analysis, Voltage Collapse, Voltage Stability Index, UPFC Device, Stability Enhancement.
Harmonic Analysis of Power Systems in order to Network Conversion
by R.
Shariatinasab, M. Akbari
Vol. 4. n. 6, pp. 3125-3134
Abstract -
Conversion of 3-phase single-circuit (3PSC) to 3-phase double-circuit
(3PDC) and 6-phase single-circuit (6PSC) transmission line is a well
known method to increase the power transfer capability of the network.
The constraints using to decide on conversion type are usually network
total loss and desirable voltage limits; while the harmonic effects are
omitted. However, harmonics lead to undesirable power quality and
increase total loss of the network. Thereby, in order to obtain the
accurate result to adopt an optimal scheme for network conversion,
harmonics should also be considered. In this paper a harmonic analysis
due to the conversion of 3PSC to 3PDC and 6PSC network is performed. The
analysis is applied to a real study system by conversion of the entire
and just one of the existing lines of the network, separately. The
results show that, when harmonic effects are considered or omitted, the
criteria needed to make a decision on the options existed for network
conversion could change. Due to the obtained results, telephone
influence factor (TIF) of currents and total harmonic distortion (THD)
of voltages are dependent on conversion type together with the harmonic
sources of the network. However, in 6PSC conversion compared to 3PDC
conversion type, the number of resonances is increased and propagation
of high frequency disturbances is decreased.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Harmonic Analysis, Network Conversion, Current TIF, Voltage THD.
Harmonics Reduction
Techniques – a Survey
by
Hadeed Ahmed Sher, Ali M. Eltamaly
Vol. 4. n. 6, pp. 3135-3147
Abstract - With the
growing progress in the field of power electronics the issue of power
quality come up with an important area of research. The unsaturated
progress of power electronics has certain pros and cons also. The most
vital among the disadvantages of power electronic loads are the
production of harmonics. A lot of work is going on in the scientific
community for the enhancement of power quality. Several strategies have
been devised to reduce harmonics. With the advent of artificial
intelligence (AI) and expert system (ES) based techniques, the
researchers are better able to optimize the harmonic filters. Active
filters have been surveyed by some researchers, however, so far no
collective survey on harmonic reduction techniques is available. In an
attempt to contribute with the scientific community, this paper
discusses the major harmonic reduction techniques available in
literature.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Harmonics, Passive Filters, Current Reinjection, Active Filters, Power Quality.
Optimal Allocation and Sizing of DG on Distributed Network for Voltage Profile
Improvement and Voltage Imbalance Reduction with Genetic Algorithm
by M. Sarvi, S. M.
Torabi, A. Fallahpisheh
Vol. 4. n. 6, pp. 3148-3154
Abstract -
Progresses made in distributed generation (DG) technologies and utilizing them
on distribution network, prepare an opportunity to impart of their utilizing
benefits in operation improvement of distribution networks. The benefits of
using these resources are such as loss reduction voltage profile improvement,
network reliability improvement, and etc. Progresses made in distributed
generation (DG) technologies and utilizing them on distribution network, prepare
an opportunity to impart of their utilizing benefits in operation improvement of
distribution networks. The benefits of using these resources are such as network
reliability improvement, loss reduction, voltage profile improvement and etc. To
achieve the desired aims, sitting allocation and sizing problem that means
determining capacity, number and location of DG is very important. In this
paper, an optimal DG resource sitting via genetic algorithm is proposed in order
to improve voltage amplitude and imbalance on distribution networks. In other
words, objective is to adjust bus voltage amplitude to desired values (usually
nominal values) along with voltage imbalance reduction via optimal DG resource
sitting. The effects of DG resource on loss and voltage profile within
distribution network are investigated and then the proper load flow on the
presence of DG resources is presented. Simulation results are performed in the
MATLAB software. Two networks (the symmetrical IEEE 13 buses and asymmetrical 26
buses) are investigated and their results are analyzed. The accuracy and benefit
of the proposed method for determination of capacity, number and location has
been shown in simulation results.
Copyright © 2011 Praise Worthy Prize S.r.l. -
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Keywords: Distributed Generation, Optimal Allocation and Sizing, Voltage Profile, Voltage Imbalance.
Proposed Optimal Multiplier Load Flow Method for the Maximum Loading Point
Search in Ill Conditioned System
by A. Shahriari,
H. Mokhlis, A.H.A. Bakar, H.A. Illias
Vol. 4. n. 6, pp. 3155-3163
Abstract - The
accuracy of the classical optimal multiplier power flow method in the
feasible and infeasible operation zone in ill conditioned system is
relevant to the exact value of the Maximum Loading Point (MLP). The
optimal multipliers are forced to meet each other at MLP. Therefore,
there is no guarantee that the optimal multiplier leads to a voltage
collapse point of a system at MLP. This paper presents a new robust,
simple and fast approach based on the optimal multiplier load flow
method (OMLFM) to detect MLP. The proposed method introduces the
divergence of the second order terms of OMPFM as a detector to obtain
MLP. The advantages of this method compares to previous techniques are:
1 - Calculation of low voltage solution of a system and their
corresponding MLPs simultaneously for the boundary zone of an ill
conditioned and unsolvable system. 2 - No new computation for OMLFM in
obtaining the MLP. 3 - The utilization of fully polar coordinate system
instead of rectangular coordinate, which further simplifies the task and
by keeping PV type buses, this method is more appropriate for power flow
solution in ill conditioned system.
This method is validated by using 300 IEEE bus system.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Maximum Loading Point, Low Voltage Solution, Ill Conditioned System.
Capacitor and DG Placement in Distribution System by Genetic Algorithm and PSO
by M. Sarvi, S. M.
Torabi, M. R. Salimian
Vol. 4. n. 6, pp. 3164-3168
Abstract -
Distributed generation (DG) and capacitors are important tools in
distribution system which can be used to improve the system voltage and
reduce system losses. Optimal sizing and siting of DG and capacitors
must be determined in distribution system. In this paper, we use genetic
algorithm and PSO for Optimal sizing and siting of DG and capacitors.
Effect of DG and capacitor on loss reduction, reactive generation and
voltage regulation are compared. Also genetic and PSO are compared.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: DG, Capacitor, Loss, Reactive, Voltage.
Optimization of Distributed Generation Number, Location and Sizing for
Reliability Improvement and Line Loss Reduction Using PSO
by Y. Bostani
Amlashi, H. Afrakhte
Vol. 4. n. 6, pp.
3169-3174
Abstract -
Distributed Generation (DG) is providing the electricity power near the
point of consumption by omitting the incremental costs. There is an
increasing trend towards DG application in power systems because of
compensating the load congestion, improving the capacity of transmission
lines, increasing power quality and greater reliability. Accordingly in
this study a new methodology has been presented that uses a particle
swarm optimization (PSO) algorithm for specifying the reliability
improvement and power loss reduction. By means of this method can
determine the optimal number, location and sizing of distributed
generation unites in a radial distribution system. Reliability Indexes
is also enhanced while the losses decrease in the network. The submitted
method is tested on standard IEEE 33-bus test system and the results are
presented to exhibit the efficiency of the proposed procedure.
Copyright © 2011 Praise Worthy Prize S.r.l. -
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Keywords: Distributed Generation; Distribution Networks; Particle Swarm Optimization (PSO); Power Loss; Reliability.
Design of TCSC Controller for Improvement of Transient Stability of a Power
System
by P.Nagaraju
Mandadi, Dr. K.Dhanvanthri
Vol. 4. n. 6, pp. 3175-3179
Abstract - FACTS
controllers , because of their fast response, improves the Transient
Stability limit of a power System by giving away the excess energy
gained by the generators in the event of disturbances due to faults.
Thyristor controlled Series Compensator (TCSC) is an important device in
FACTS family and is widely recognized as an effective means to solve the
power system stability problem. In the present work, a SIMULINK setup
has been developed by means of which the parameters of TCSC controller
along with a Power System Stabilizer (PSS) can be selected and designed
to get a desired time response. The developed SIMILINK setup is Robust,
Easy and Simple which can be used to determine the parameters very
quickly thereby saving a lot of time.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Transient Stability, FACTS Controllers, Thyristor Controlled Series Compensator (TCSC), Power System Stabilizer (PSS), Simulink, Matlab.
Locating and Parameter Setting of Unified Power Flow Controller via Harmony
Search Algorithm
by A. Sharifi
Nasab Anari, R. Ghadiri Anari, S. Soleymani, M. Ghasemi Nezhad
Vol. 4. n. 6, pp. 3180-3187
Abstract - This
paper proposes a Harmony Search Algorithm (HSA) to achieve the optimal
location and proper parameters settings of Unified Power Flow Controller
(UPFC) for congestion Management in restructured electricity market.
Having a great flexibility, UPFC can control the active and reactive
power flow and bus voltages, simultaneously. Two different objective
functions are considered in this study. In the first one, minimization
of total operating cost including congestion rent and total generation
cost is considered as the objective function. In the second one,
objective is minimization of system loss. In order to verify and
validate the effectiveness of the proposed method, IEEE 14-bus test
system and IEEE Reliability Test System (RTS) are employed. The results
for IEEE RTS are compared with those obtained by PSO algorithm, reported
in the literature. The results show that the congestion cost and loss of
the power transmission system can be effectively reduced through the
optimal location and proper parameters selection of the UPFC.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Power System Loss, Unified Power Flow Controller (UPFC), Harmony Search Algorithm, Congestion Management.
Thermal Unit Commitment Scheduling Problem in Utility System by Simulated
Annealing Embedded Evolutionary Programming Method
by Nimain Charan
Nayak, C.Christober Asir Rajan
Vol. 4. n. 6, pp. 3188-3194
Abstract - This
paper presents a new approach to solving the short-term thermal unit
commitment scheduling problem in utility system using Simulated
Annealing Embedded Evolutionary Programming Method. The objective of
this paper is to find the generation scheduling such that the total
operating cost can be minimized, when subjected to a variety of
constraints. A 7-Unit utility power system with twelve generating units
in India demonstrates the effectiveness of the proposed approach;
extensive studies have also been performed for different IEEE test
systems consist of 10, 26 and 34 Units. Numerical results are shown
comparing the cost solutions and computation time obtained by using the
Evolutionary Programming method and other conventional methods like
Dynamic Programming, Legrangian Relaxation and Simulated Annealing in
reaching proper unit commitment.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Unit Commitment, Simulated Annealing, Evolutionary Programming, Dynamic Pogramming, Legrangian Relaxation.
Electric Field Computation for Functionally Gradient Material Spacer Insulator
for Gas Insulated Bus Duct
by Gopichand
Naik.M, Amarnath.J , Kamakshiah.S
Vol. 4. n. 6, pp. 3195-3200
Abstract - The Gas
Insulated Substation (GIS) have various advantages like compactness,
immunity from environmental conditions, high operational reliability,
low maintenance cost. In a number of GIS installations, the main design
considerations involved in gas insulated equipment are at cone
insulator, gas and metal interface. Hence there is a need for control of
electric stress in order to reduce internal discharges, surface
discharges to the enclosure surface. In conventional approach, in order
to reduce such distortion of electric field, many techniques applied
like, control of the spacer shape, additional shielding of electrodes
for relaxation of electric field around spacer and low permittivity
material of spacer, etc., from this point of view the new techniques of
Functionally Gradient Material (FGM) spacer has been proposed in this
paper. The applicability of FGM spacer for gas insulated power apparatus
has been verified. In the FGM spacer, a spatial distribution of
permittivity for the control of the electric field distribution in and
around the spacer is used. The electric field calculations for several
types of FGM spacers have been carried out using Finite Element Method
(FEM). The electric field distribution along the radial distance of the
spacer insulator has been obtained for various FGM materials and results
are compared.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: FGM, FEM, Electric Field Distribution, Modelling of Cone Spacer.
Preventive and Curative Strategies Based on Fuzzy Logic Used for Voltage
Stabilization of an Electrical Network
by Moez Ben
Hessine, Sahbi Marrouchi, Souad Chebbi, Houda Jouini, Rabeh Abbassi
Vol. 4. n. 6, pp. 3201-3207
Abstract - In this
paper, we present the new preventive and curative strategy developments
used to a power system stability control implemented in the network Test
IEEE 14 buses. This development is in order to show that this type of
control ensures maintenance of the network in a study state by using an
adequate control taking into account of the studied network state
variable instantaneous specificities in the presence of a disturbed
mode. The best identification of algebraic and dynamic state variable
variation margins of the studied system specifically in disturbed mode
will be at the origin of new control strategy integration able to
contribute effectively to a network new study state establishment. Our
control strategies are proposed to estimate of the electric quantity
variation margins (active power and reactive power) injected at any bus
particularly in case of rare event appearances. We exploited fuzzy
controllers in order to generate an adequate command vector taken as an
optimized action to prevent such electrical network situation.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: FACTS, UPFC, Fuzzy Logic, PSRF, NSRF, PLL, PWM, Positive Sequence, Negative Sequence, Load Shedding, Sensitivity.
Different Methodologies to Determine Break Point Relays in a Power System
Protection
by Joymala
Moirangthem, S. S. Dash, A. F. Zobaa
Vol. 4. n. 6, pp. 3208-3213
Abstract -
Coordinating a system of directional relay is very complicated due to
the typical loop structure of the transmission system, and also changing
the setting parameters of one relay for obtaining coordination for all
the relevant fault current pairs can disturb the proper coordination of
the already checked relay pairs. Arbitrary starting relay locations and
arbitrary consideration of relay sequence to set and coordinate relays
will result in navigating loops many times, and usually result in futile
attempts to achieve system-wide relay coordination. This paper has
listed out the different methodologies and techniques to determine the
break point set to provide accurate directional relay coordination. And
also new technique Particle swarm optimization has been introduced and
implemented to determine the break point relays in this paper. This work
will be useful for the researchers to find the relevant references to
enhance the research work in future.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Break Point Set (BPS), Looped System, Particle Swarm Optimization (PSO), Relay Coordination, Relay Settings.
A Review of Methodologies for Fault Detection and Location in Distribution Power
Networks
by A.C. Adewole,
R. Tzoneva
Vol. 4. n. 6, pp. 3214-3231
Abstract - The
widespread deregulation and restructuring of electric power utilities
throughout the world and the consequent increase in competition amongst
utility companies has brought about the desire for improved economic
efficiency of electric utilities and the provision of better service to
energy consumers. Thus, there is a growing research interest in power
system distribution network fault detection and diagnostic techniques.
Transmission and distribution lines are subject to faults caused by
lightning, storm, snow, insulation breakdown, birds, etc. Fault
detection and diagnosis is a central component of Abnormal Event
Management (AEM). The early detection and diagnosis of these faults can
expedite the restoration and return to service of this lines. This paper
provides a comprehensive review of research work on the various
methodologies in power system distribution network fault detection,
fault classification, faulted section identification, and fault
location.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Artificial Neural Network, Distribution Network, Fault Detection, Fault Location, Power System Protection.
International Review on Modelling and Simulations - Papers (Part C)
Effect of Crack Faces Opening Mechanisms on the Combined Stress Intensity
Factors under Bending and Torsion Moments
by A. E Ismail,
A.K Ariffin, S. Abdullah, M.J Ghazali
Vol. 4. n. 6, pp. 3232-3238
Abstract - This
paper presents a numerical investigation on the effect of crack faces
opening mechanisms on the combined stress intensity factors for surface
cracks in round bars. A full finite element model was constructed due to
the non-symmetrical analysis involved. Bending and torsion moments were
remotely applied to the model and the stress intensity factors were
calculated along the crack front. The stress intensity factors were also
combined explicitly through the equivalent stress intensity factor
method and then compared with the results obtained from the finite
element analysis under combined loadings. There were high discrepancies
between the results especially when the bending moment dominated the
stress condition. From the deformed mesh observation, it was found that
the discrepancies were due to the differences in crack face interaction
mechanisms and thus affecting the combined stress intensity factor
calculations.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Combined Stress Intensity Factors, Finite Element Analysis, Surface Cracks.
EMTP-RV Model of
Hydraulic Digital Governor
by M. Dabro, I.
Jurić-Grgić, R. Lucić
Vol. 4. n. 6, pp. 3239-3242
Abstract -
This paper presents EMTP-RV model of hydraulic digital governor. Based
on block scheme of a digital turbine control system, a novel EMTP-RV
model of hydraulic digital governor for stability studies has been
developed. Developing of hydraulic digital governor is an important step
in achieving a fully integrated system for stability studies. The
simulated transient response characteristics of a digital governor,
obtained by the proposed model, give us much more realistic response
comparing to the conventional hydraulic governor model (IEEE Type 3
turbine and governor system).
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: : Hydraulic Digital Governor Model, EMTP-RV.
Emission Controlled Security Constrained Unit Commitment Considering
Hydro-Thermal Generation Units
by M. S. Javadi,
A. Meskarbashi, R. Azami, Gh. Hematipour, A. Javadinasab
Vol. 4. n. 6, pp. 3243-3250
Abstract - In this
paper, Emission Controlled Security Constrained Unit Commitment (ECSCUC)
model is proposed in power system. This model consists of a closed-loop
modified Unit Commitment (UC) and Security-constrained Optimal Power
Flow (SCOPF). An emission controlled formulation is developed to improve
the economic-environment conditions of operation of power system. The
objective of this ECSCUC model is to obtain the maximum social
welfare-based system operating cost while maintaining the system
security also considering the environmental impacts. This paper proposed
a multi-stage multi-objective mixed-integer nonlinear programming (MINLP)
to minimize system operation cost. In this paper, multi-reservoir
cascaded hydro plant with time delay and thermal plants are considered
for maintaining the demand. The presented formulation treats emission
controlled security constrained unit commitment of hydrothermal power
system which attempts to optimize both cost and emission simultaneously.
The numerical examples exhibit the effectiveness of the proposed model
in recent competitive electricity markets.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords:
Hydro-Thermal Generation Units, Emission controlled Security
Constrained Unit Commitment, Cascaded reservoirs.
Development
of an Inertial Measurement System for Electronic Stability Control Applications
by V.
Mahboubi, M. Khoddam, H.Badri, A.Ebrahimi
Vol. 4. n. 6, pp. 3251-3260
Abstract - In this
scheme, after assessing the requirements of electronic stability
systems, in addition to a sensor set including a yaw-rate sensor, an
accelerometer, a thermal sensor and an speed sensor, a 32-bit
microcontroller based control system was designed in which the major
necessities for data collecting and rapid processing of such a typical
system could be performed. Furthermore, hardware capabilities for
implementing the control algorithms using appropriate actuators when
installing on a mechanical system was considered. Simultaneously, system
is able to connect through the serial interfaces to the more powerful
computers and processors for more complicated analysis. Moreover, for
evaluating the performance of the designed system, a mechanical
test-bench was designed and the obtained data was compared with the
computer simulations. Results show that the designed inertial
measurement system meets the required specifications of speed,
efficiency and reliability.
publication by IREE.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Gyroscope, Accelerometer, Microcontroller, Crank-Rocker Mechanism, Electronic Stability Control.
Selecting Suitable Journal in Digital Libraries with Web Usage Mining
by Farzam Yousefi,
Sayed Mehran Sharafi, Mohammad Ali Nematbakhsh
Vol. 4. n. 6, pp. 3261-3272
Abstract - One of
the existing sources in digital libraries is electronic journals.
Librarians use e-journals’ usage data for many practical applications
(e.g. to begin or end subscriptions). Publishers and vendors, who have
these data, usually don’t share them with the librarians or represent
only that data which support their sales products. One possible method
for evaluation is preparing monitoring system and logging the data
related to users’ interactions with digital library and collecting
transactions and using data analyzing techniques. In this research web
usage mining method has been used. Since server log files don’t contain
precise information and details of users’ interactions, this research is
going to use client side data, special new category of data called
Intentional Browsing Data(IBD), for improving quality of discovered
knowledge and exploit IBD as a criterion for determining the journals’
desirability in students’ viewpoint.The obtained knowledge from
analyzing discovered patterns can be used to make decision in journal
management and it is a new method in this field. Digital library of
Islamic Azad University of Najaf Abad (IAUN) is considered as a
practical domain of this research. By using obtained patterns of mining
and analyzing collected data, a model is presented to identify
desirability of journal according to students’ viewpoint.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Digital Libraries, Intentional Browsing Data, Usage Data, Web Usage Mining.
Matlab Based Fluid Level Control Using Pid and Fuzzy Logic Controllers
by Abdurrahman
Ünsal, Ahmet Kabul
Vol. 4. n. 6, pp. 3273-3278
Abstract - In this
paper, fluid level control system was designed by using PID control and
fuzzy logic control algorithms in MATLAB&Simulink environment. The
communication between the hardware of the system and Simulink program
was established by using automatic code production tool which is a part
of the MATLAB Real Time Workshop toolboxes. PID control and fuzzy logic
control algorithms were applied to the designed system. The comparison
was made between these two methods. The results of the methods are
compared. The experimental results show that the system reaches its
steady state position when controlled by using fuzzy logic method.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Fluid Level Control, Fuzzy Logic Controller, PID Controller, Real Time Control.
A New Time-Domain H2-Norm Robust Fault Detection Filter for a Drum
Boiler System through an LMI Approach
by L. Khoshnevisan
Vol. 4. n. 6, pp. 3279-3284
Abstract - One of
the robust fault detection filter (RFDF) designing methods is based on H2-norm
technique. The fundamental purpose of our study is to formulate the RFDF
as a continuous robust H2-norm optimal design via a linear matrix
inequality (LMI) through which the generated residual signals are robust
against external disturbances and sensitive to faults simultaneously.
The designed RFDF is continuous with the advantage of not mandating any
transformation matrix and can directly be implemented to the time-domain
original continuous model. Finally, the designed method is theoretically
applied in a simulated model of a drum boiler operating in Synvendska
Kraft AB Plant in Malmo, Sweden as a multivariable and strongly coupled
system. It is illustrated that both sensor and actuator faults can
robustly be detected as quickly as possible. Also sensor faults can be
isolated through this procedure. To the best author's knowledge, this is
the first time that the continuous H2-norm procedure is
applied to detect actuator and sensor faults in a real boiler.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Boiler, Continuous H2-Norm Filter, Fault Detection, Linear Matrix Inequality, Robustness.
Fuel Cell and Solar Cell Hybrid System for Electrical Energy Generation
by Sazzad Hossain,
Farzana Sharmin, Mohiuddin Ahmad, I. Daut, M. A. Rashid
Vol. 4. n. 6, pp. 3285-3291
Abstract - The
storage of fossil fuel is being reduced rapidly to meet the present
demand of energy all over the world. This will obviously result in the
scarcity of usable fuel and hence energy in near future if we don’t find
any viable solution very soon. Keeping this in mind, in our research
paper we tried to find a possible solution of the energy crisis by
developing a self-dependent power generation system. This is actually a
hybrid system involving fuel cell and photovoltaic cell. Here, fuel cell
is used as the base technology along with photovoltaic cell. We have
utilized the hydrogen of water as the fuel source of fuel cell. The type
and number of fuel cell stacks are so chosen that the system has the
capability of providing necessary power requirements to a single house
and can run by itself. The system described here is self-sufficient,
environment friendly and safe. So it can play a vital role in solving
the current energy problem quite satisfactorily.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Fuel Cell, Solar Cell, Electricity Generation, Converter Circuit.
Analyzing the
Properties of Mobius Capacitors
by Eraldo Banovac,
Sejid Tesnjak, Darko Pavlovic
Vol. 4. n. 6, pp. 3292-3300
Abstract - A
theoretical foundation crucial for the physical processes that occur
when the mobius capacitor is connected to the AC circuit is elaborated
in the paper. A thin copper sheet and the PVC adhesive insulating tape
are formed into different types of capacitors with the aim of
researching the properties of the mobius capacitor, and testing its
capacitance. The obtained capacitance values of the mobius capacitors
with a pair of capacitive enclosures are stable, i.e. 3.7 pF and 4.0 pF
for the first system, and 27.3 pF and 27.5 pF for the second system with
the larger conductive strips. The properties of the mobius capacitor
connected to an AC circuit are tested. The capacitance of the capacitor
is calculated indirectly from the data obtained by measuring in the
circuit. The paper points out that the mobius capacitor operates in the
AC circuit likewise the parallel plate capacitor. The distance between
the conductive strips is variable because of the elasticity of the
dielectric strip, so that the capacitance of the capacitor is easily
influenced by squeezing the strip or by gradual relaxation of the strip.
Therefore, less precision of measurement of capacitance of the mobius
capacitor in relation to the parallel plate capacitor is obtained, such
as evident from the calculated values of the measurement errors.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: AC Circuit, Capacitance, Mobius Capacitor, Mobius Resistor.
Development of the Lightning Location Mapping System Using Fuzzy Logic Technique
by A. Che Soh, R.Z.
Abdul Rahman, M.Z.A. Ab. Kadir, N.S. Mohd Shif
Vol. 4. n. 6, pp. 3301-3308
Abstract - The
extremely high current produced from the lightning strike causes damages
to the structures and fatalities to the human and live stock.
Information regarding the lightning strikes and the location where it
strikes is very useful for the utilities and building developers to
select the best location of the project and the most suitable protection
scheme for their system. The objective of this paper is to develop a
Graphical User Interface (GUI) which can classify the lightning
parameters of Peninsular Malaysia into three characteristics: region,
level of current and type of lightning. The lightning strike parameters
were obtained from the Global Lightning Network (GLN) of WSI
Corporation, USA. Fuzzy logic method is used to classify the Peninsular
Malaysia into eight regions with the use of ‘IF rule’ to determine the
level of current and type of lightning strikes. The lightning parameters
are classified into three levels of current: Low, Medium and High
current with three different types of lightning: positive lightning,
flash and negative lightning. The GUI of desired system is implemented
using Microsoft Visual Basic which able to display the characterization
process, statistical values, graphs and also the characteristics mapping
for the corresponding regions.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Lightning, Lightning Parameters, Global Lightning Network, Fuzzy Method.
Gantry Robot Control with an Observer Based on a Subspace Identification with
Multiple Steps Data
by A. Bouhenna, A.
Chenafa, A. Mansouri, A. Valera
Vol. 4. n. 6, pp. 3309-3316
Abstract - When
working with complex dynamic systems such as robotic systems needs to have a
good estimate of the various terms that make them dynamic equation. From this
estimate may provide various control algorithms (usually nonlinear) to
compensate or take into account this dynamic equation. The problem that often
arises is twofold: one part is not trivial to obtain the dynamic terms, and
secondly, the control algorithms usually have high complexity, which may make it
impossible to implement them in real time environments. This paper deals with
obtaining the system state estimation using subspace-based system identification
that not only get an estimate, but also can be used to calculate and implement
control algorithms. This method has been validated on a gantry robot with
multiple data sets. We have also designed a optimal control with a state
observer using the estimated state space systems of the gantry robots. The
results are very satisfactory.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Subspace Methods, System Identification, N4SID, MOESP, Discrete State Space, Gantry Robots, Optimal Control Algorithms, State Observer.
Designing Intelligent Advanced Controller for a Class of Large Scale
Non-Canonical Nonlinear Systems: Observer-based Approach
by R. Ghasemi,
M.B. Menhaj
Vol. 4. n. 6, pp. 3317-3326
Abstract - This
paper introduces a new decentralized adaptive fuzzy controller for a
class of large-scale nonlinear systems with unknown non-affine
subsystems and unknown interconnections represented by nonlinear
functions. The fuzzy system is used to represent the controller's
structure. The stability of the closed loop system is guaranteed through
Lyapunov stability analysis by introducing some adaptive rules derived
appropriately. Simulation results easily highlight merits of the
proposed controller.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Lyapunov Stability - Adaptive Control- Non-affine Nonlinear Systems- Large Scale Systems- Fuzzy Systems – Nonlinear Observer.
Adaptive Gain Scheduling Fuzzy Logic PID Controller in Load Frequency Control of
Wind Diesel Micro Hydro Isolated Hybrid Power System
by R.Dhanalakshmi,
Dr.S.Palaniswami
Vol. 4. n. 6, pp. 3327-3336
Abstract - This
paper presents the design and analysis of Adaptive gain scheduling Fuzzy
logic PID controller for load frequency control of an isolated
wind-diesel micro hydro hybrid power system, to regulate the frequency
deviation. Due to the sudden load changes and intermittent wind power,
large frequency fluctuation problem can occur. An effective controller
for maintaining the system frequency within acceptable range is
significantly required . The fuzzy logic control has been applied to
design LFC system. The proposed adaptive gain scheduling Fuzzy logic PID
controller automatically tunes the coefficients Kp, Ki and Kd whenever
there are load disturbances. Also, a conventional proportional Integral
(PI) controller and a fuzzy logic (FL), controllers were used to control
the same hybrid power system for the performance comparison. Simulations
of the proposed Adaptive gain scheduling Fuzzy logic PID controller in
an isolated wind diesel micro hydro hybrid power system with different
load disturbances and with wind disturbances are performed. The proposed
Adaptive gain scheduling Fuzzy logic PID controller provides best
control performance over a wide range of operating conditions. The
performance of the proposed approach is verified from simulations and
comparisons. Simulation results explicitly show that the performance of
the proposed Adaptive gain scheduling Fuzzy logic PID controller is
superior to the conventional PI controller and fuzzy logic controller
against various load changes and variations of wind inputs.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Load Frequency Control, Wind Diesel Micro Hydro Hybrid System, Adaptive Gain Scheduling Fuzzy Logic PID Controller, Proportional Integral Controller, Fuzzy Logic Controller.
Modelling, Simulation and Analysis of a 5-dof Planar Parallelogram–link Biped
Mechanism
by Carla Campos,
Ricardo Campa, Miguel Llama, Alfonso Pámanes
Vol. 4. n. 6, pp. 3337-3352
Abstract - This
paper reports the modelling, trajectory planning and control of a
5-degree-of-freedom biped robot with parallelogram-type links that is
being designed and built in the Instituto Tecnológico de la Laguna,
Mexico. The kinematic and dynamic models are obtained by using a
simplified approach of the real mechanism. The model-based controller
for the tracking of the proposed gait patterns, and the analysis of the
Zero Moment Point, which determines the dynamic stability, are also
presented. Simulation results give important information for the
practical implementation of the mechanism.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords:
Biped Robot, Kinematics, Dynamics, Computed-Torque Control,
Zero-Moment Point.
Computation of Electric Field and Potential Distribution around a Polluted
Porcelain Insulator by Boundary Element Method
by
K.Krishnamoorthi, S.Chandrasekar, D.Pradhap
Vol. 4. n. 6, pp. 3353-3360
Abstract - This
paper presents the simulation results of electric field and potential
distributions along surface of porcelain insulator by two –dimensional
boundary element method(BEM).In this work, 2D Electrostatic software
based simulation was carried out on 11 KV porcelain insulator at
different conditions. Clean and various contamination conditions with
and without water droplets. The simulation results show that
contaminations have no effect on potential distribution along the
insulator surface while electric field distributions are obviously on
contamination conditions.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Electric Field Distribution, Potential Distribution, Porcelain Insulator, Boundary Element Method.
Fuzzy Pattern
Recognition Based Fault Diagnosis
by Rafik Bensaadi,
Leïla H. Mouss, Mohamed D. Mouss, Mohamed Benbouzid
Vol. 4. n. 6, pp. 3361-3370
Abstract - In order
to avoid catastrophic situations when the dynamics of a physical system
(entity in Multi Agent System architecture) are evolving toward an
undesirable operating mode, particular and quick safety actions have to
be programmed in the control design. Classic control (PID and even state
model based methods) becomes powerless for complex plants (nonlinear,
MIMO and ill-defined systems). A more efficient diagnosis requires an
artificial intelligence approach. We propose in this paper the design of
a Fuzzy Pattern Recognition System (FPRS) that solves, in real time, the
main following problems: 1) Identification of an actual state; 2)
Identification of an eventual evolution towards a failure state; 3)
Diagnosis and decision-making. Simulations have been carried for a
fictive complex process plant with the objective to evaluate the
consistency and the performance of the proposed diagnosis philosophy.
The obtained results seem to be encouraging and very promising for
application to fault diagnosis of a real and complex plant process.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Diagnosis, Fault Detection, Pattern Recognition, Fuzzy Control, Conjugate Gradients, Complex Plant Process.
Smart Assisting Device for Partially Paralyzed People during Locomotion-Design
and Control
by
T.S.Sirish, K.S.Sivanandan
Vol. 4. n. 6, pp. 3371-3375
Abstract - In the
present living conditions people with disabilities (lower limb weakness) are
increasing day by day. In order to assist the simple daily activities of those
people an assistive device is designed. The device developed is used to support
the user to perform the normal walking without the use of his hands (crutches),
so that he can do other activities during walking with hands. The device will
support the user during the stance and swing phase of gait by locking the knee
during stance phase and unlocking during swing phase. Stepper motors are used to
lock and unlock the knee automatically during human locomotion. A driving
circuit is designed using PIC to synchronize the activities. A feed back
technique is used to make the operation automatic.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Assistive Device, Gait Posture, Human Locomotion.
Wind-PV-Grid Connected Hybrid Renewable System in Kish Island
by Arash Anzalchi,
Babak Mozafari
Vol. 4. n. 6, pp. 3376-3382
Abstract - This
study presents an analysis of the technical and financial viability of
grid/RES hybrid power supply configurations for a touristy Island.
Assessment criteria comprised net present cost (NPC), cost of energy
(COE) and green house gases (GHG) reduction. The RES software HOMER
(National Renewable Energy Laboratory, US) was utilized as the
assessment tool with modeling performed with hourly load data input from
Kish Island in tropical area of Hormozgan, Iran. As Kish is not
connected to grid, price of a submarine transmission system is entered
as the fixed capital cost of the system. Grid connection is required as
energy backup and as well to make the system commercial. If the
electricity produced by the renewable energy sources was not enough to
supply the Kish's demand, the required energy would be supplied by
purchasing energy from the grid. Otherwise, if the energy produced by
RES excesses the load of Kish Island, the excess energy would be sold to
the grid.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: PV Panel, Wind Turbine, Renewable Energy, Cost of Energy.
Coupled-Mode Analysis of a T-branch Waveguide with a Wavelength-Selective
Reflection Feedback
by K. Fasihi
Vol. 4. n. 6, pp. 3383-3387
Abstract - The
operation of T-branch waveguides with a wavelength-selective reflection
feedback is analyzed using theoretical and numerical analysis. The
coupled-mode theory (CMT) is employed to drive the necessary conditions
for achieving perfect transmission. The analytic results reveal that the
reflection to the input port is absent when the phase-shift of the
electromagnetic waves traveling between the cavities is equal to (2n+1)
π/2 and the decay rates into the three ports are equal. The
finite-difference time-domain (FDTD) simulation results of the modified
T-branch which is implemented in two dimensional photonic crystals
(2D-PC), show that the analysis is valid. The proposed structure might
also be valuable for design of other integrated optical functions.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Coupled-Mode Theory (CMT), Finite-Difference Time-Domain (FDTD), T-Branch Waveguide, Photonic Crystal (PC), Attenuator, Wavelength-Selective Reflector.
Prediction of Module Operating Temperatures for Free-Standing (FS) Photovoltaic
(PV) System in Malaysia
by H. Zainuddin,
S. Shaari, A.M. Omar, S.I. Sulaiman, Z. Mahmud, F.Muhamad Darus
Vol. 4. n. 6, pp. 3388-3394
Abstract - Numerous
thermal models have been developed to predict the photovoltaic (PV)
module operating temperature (Tm) mainly in the high latitude regions.
Only a few has been developed in tropical region, specifically Malaysia.
However, none of these studies have quantified the effect of humidity in
predicting Tm despite the other widely used ambient variables.
Therefore, in this study a new multiple linear regression (MLR) Tm model
(HZ1) with four ambient variables; namely plane-of-array irradiance,
ambient temperature, wind speed and relative humidity is proposed. The
accuracy, validity and suitability were analyzed and compared with
Sandia National Laboratory (SNL) model and Nominal Operating Cell
Temperature (NOCT) model for free-standing (FS) PV system in Malaysia.
Mean absolute percentage error (MAPE) and root mean square error (RMSE)
were used as error measures and R2 was determined as coefficient of
determination of the three aforementioned models for comparison. As a
conclusion, the new proposed model (HZ1) is more accurate than SNL and
NOCT models in predicting PV module operating temperature for FS PV
system in Malaysia.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Module Operating Temperature, Free-Standing, HZ1 Model, SNL Model, NOCT Model.
A Study on Duffing Oscillator’s Ability on Detecting Disappearance of the
Detected Weak Signal
by V. Rashtchi, M.
Nourazar
Vol. 4. n. 6, pp. 3395-3401
Abstract - After the
successful use of duffing oscillator in weak signal detection, many
researches are done on this subject. Most of these studies only analyze
the efficiency of duffing oscillator on detecting the existence of weak
signal and they ignore to study duffing oscillator’s ability on
detecting the loss of signal that was already detected. Considering
this, we are going to analyze this ignored issue. In this paper we
introduce two methods to add this ability to duffing oscillator.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Weak Signal Detection, Duffing Oscillator, Largest Lyapunov Exponent, Oscillator Resetting.
Performance Comparison of Dynamic Models of Proton Exchange Membrane and Planar
Solid Oxide Fuel Cells Subjected to Load Change
by N. A. Zambri,
A. Mohamed, H. Shareef
Vol. 4. n. 6, pp. 3402-3409
Abstract - The
depletion of fossil fuel, rise in oil prices, increase in power demand
and environmental concerns has led renewable energy to be an alternative
energy option. Among the various types of renewable energy, fuel cell
technology shows a great potential in electrical energy sector due to
several reasons such as high efficiency, clean operation, and immune to
weather conditions. Fuel cell is an electrochemical device that converts
chemical energy of a reaction directly into electrical energy and can be
categorized as a high grade electricity source because of its ability to
produce constant power at full load. This paper presents mathematical
modeling and simulation study of proton exchange membrane and planar
solid oxide fuel cells by using Matlab/Simulink software. The main
objective of this paper is to compare the simulation results of the two
fuel cell types which stated earlier. Simulation results show that
proton exchange membrane fuel cell has higher voltage capacity and power
density while planar solid oxide fuel cell gives better performance for
the step load current changes.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Proton Exchange Membrane Fuel Cell, Planar Solid Oxide Fuel Cell, Dynamic Model.
Design and Analysis of a Composite Cone Type Spacer in Gas Insulated Systems
under Various Abnormal Conditions Using Finite Element Method
by D.Deepak
Chowdary, J.Amarnath
Vol. 4. n. 6, pp. 3410-3417
Abstract - –
Interfaces formed by gas dielectric and solid insulating spacer
represent the weakest point in Gas Insulated Systems (GIS). It is
essential to determine the electric field distribution along the spacer
surfaces and evaluate the degree of their reliability. A key aspect in
the design and optimization process of insulating spacers is the precise
simulation and geometric optimization of the electric field distribution
on the dielectrics. The breakdown strength of GIS is strongly influenced
by the roughness of the spacer's surface like protrusions and
depressions and defects produced from improper manufacturing. One of
these forms is the loss of adhesion at electrode/epoxy interface which
leads to initiating delamination. Bulk dielectric failure of spacers can
be attributed to delamination at the electrode/epoxy interface. Electric
field distribution at the protrusions, dispersions on the surface of the
spacer, delamination and voids plays a critical factor affecting the
breakdown of spacer. Field emission from the cathode triple junction is
the primary initiating mechanism of surface flashover of insulators. In
this work, the electric field distribution on the surface of the
insulator is studied at the cathode end triple junction for a cone type
spacer with and without metal insert along with the effect of
protrusion, depression, delamination and void. The Finite Element
Method, an efficient technique for solving field problems, is employed
to compute the electric field.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Gas Insulated Systems, Electric Field Distribution, Finite Element Method.
Air Traffic Flow Modelling and Simulations Based on Dynamic Networks
by K. Bousson,
Tiago M. Domingues
Vol. 4. n. 6, pp. 3418-3424
Abstract -
Congestion in the Terminal Maneuvering Areas (TMAs) of larger airports
impacts all aspects of air traffic flow not only at national level but
may also induce arrival delays at international level. Hence, there is a
need to forecast the air traffic flow density in TMAs so that
appropriate decisions may be taken to optimize their occupancy rates.
The approach taken in the present paper relies on dynamic network
concepts for air traffic flow modelling and simulation. Indeed, the
focus has been on the predictive estimation of the number of aircraft in
specified TMAs across-time. The simulation of the described models has
been performed to validate successfully the air traffic flow dynamics
from actual and realistic data of a network of three TMAs in the Iberian
Peninsula. The modeling concepts in the present research work may help
stakeholders for TMA capacity management and optimization and subsequent
airport socio-economic policies.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Air Traffic Flow, Modelling and Simulation, Terminal Maneuvering Area (TMA), Predictive Estimation.
Performance Enhancement in Rolling Processes Using Mixed Sensor-based and
Estimation-based Control Algorithms
by Shahab Amelian,
Hamid Reza Koofigar
Vol. 4. n. 6, pp. 3425-3429
Abstract - This
paper presents a novel approach for improving the performance of rolling
mills, by designing an estimation-based control algorithm. This is
motivated by the fact that using several kinds of sensors for measuring
all of process variables is technically and economically avoided. On the
other hand, high quality may be obtained by some control algorithms at
the expense of using many sensors for exact measurement. Therefore,
there is a trade-off between high quality and technical limitations
which should be managed in such a manner that the best result is
achieved. The proposed algorithm satisfies both objectives including
high quality and low production costs by developing reduced order state
observers. The designed estimation-based control technique facilitates
combining sensor-based and sensorless design methodologies. This
technique is applicable to both hot rolling and cold rolling processes.
A typical cold rolling process is adopted here to evaluate the
effectiveness of the proposed estimation method. Simulation results show
that the desired performance can be achieved using the developed
strategy.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Reduced Order Observer, Instrumentation, Mathematical Model, Rolling Mill.
Coordination of Overcurrent Relays Using New Two Step Algorithms, a Comparative
Study Versus Classic Optimization Algorithms
by Hadi.
Hosseinian Yengejeh, Hossein. Nasir Aghdam, Hossein. Askarian Abyaneh
Vol. 4. n. 6, pp. 3430-3441
Abstract - In this
paper in order to determine the abilities and limitations of each random
search algorithm for solving overcurrent (O/C) relay coordination
problem, a comprehensive comparison is made. The algorithms which are
chosen for the comparison are; Genetic Algorithm (GA), Particle Swarm
Optimization (PSO), Immune Genetic Algorithm (IGA) and some two two step
mentioned algorithms. The convergence speed and convergence reliability
have been compared. Variation of convergence speed and the number of
points that each algorithm explore to reach global optimum point have
been also investigated. To consider equal condition, all of the
algorithms programs have been run in same computer (Pentium III 3.0
GHz). Important and effective parameters of algorithms such as
population size and initial populations range in the algorithms have
been assumed identical. The algorithms abilities have been tested on two
case studies, namely the 8 bus distribution network and 8 buss
transmission systems. It will be shown that solving the coordination
problem using some of the two step methods such as IGA–GA can be faster
than the others. From reliability of convergence viewpoint PSO have had
best performance. Success of other algorithms in this problem solving,
from various aspects have been ranked.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords: Coordination, Intelligent Methods, Overcurrent Relays.
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