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Automatic Frequency Control of a Parallel Resonant Inverter for an Induction Furnace

P. Thongprasri(1*)

(1) Department of Electrical Engineering, Faculty of Engineering at Si Racha, Kasetsart University Sriracha Campus, Thailand., Thailand
(*) Corresponding author



Main problem of an induction heating system is electrical and magnetic properties of a load changed due to the rising temperature. Consequently, resonant frequency of the load is also changed. The power transfer to the load decreases when the system cannot adjust the switching frequency to new resonant frequency. A phase locked-loop (PLL) frequency control system for the miniature induction furnace prototype is described in this paper. Automatic frequency control system of the power source capacitates continuous operation at the resonant frequency, resulting in high conversion efficiency because of zero voltage switching (ZVS) and maximum power transfer to the load at all times. Two work pieces, 13g of copper pipe and aluminum sheet, have been continuously heated by the 2kW parallel resonant inverter prototype. Experimental results, the inverter operates in resonant frequency at all the times therefore the maximum power is delivered to heated load throughout the heating time.
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Phase Locked-Loop; Zero Voltage Switching; Maximum Power Transfer

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S. Chudjuarjeen, A. Sangswang, and C. Koompai, “An Improved LLC Resonant Inverter for Induction-Heating Applications with Asymmetrical Control”, IEEE Trans on Ind Elec, vol. 58, no. 7, 2011, pp. 2915-2925.

A. R. Namadmalan, B. Abdi, and J. S. Moghani, “Current-fed parallel resonant push-pull inverter with coil flux control for induction heating applications”, Proc PEDSTC, 2010, pp.186-190.

S. Arumugam, S. Ramareddy, “A Novel Analysis of Full Bridge Series-Parallel Resonant Inverter for High Frequency Application”, Proc PES(ISGT), 2011, pp.59-64.

A. Tan, T. Demirdelen, K. C. Bayindir, and M. Tumay, “Analysis of Power Quality Problems of Coreless Induction Melting Furnace with Exact Simulation Model Based on Field Measurements”, Proc PowEng, 2013, pp.283-289.

H. Sarnago, O. Lucia, A. Mediano, and J. M. Burdio, “High-efficiency parallel quasi-resonant current source inverter featuring SiC metal-oxide semiconductor field-effect transistors for induction heating systems with coupled inductors”, IET on Pow Elec, vol. 6, no. 1, 2013, pp.183-191.

E. J. Davies , J. and P. Simpson, “Induction Heating Handbook”, McGraw-Hill, UK, 1979.

L. Grajales and F. C. Lee “Control system design and small-signal analysis of a phase-shift controlled series resonant inverter for induction heating,” Proc PESC, 1995, pp. 450-456.

N. A. Ahmed, “High frequency soft switching AC conversion circuit with dual mode PWM/PDM control strategy for high power IH applications”, IEEE Trans. on Ind. Elec, vol. 58, no. 4, 2011, pp. 1440-1448.

H. Kifune, Y. Hatanaka, and M. Nakaoka, “Cost effective phase shifted pulse modulation soft switching high frequency inverter for induction heating applications”, Proc PEA, 2004, pp. 19-25.

N. J. Park, D. Y. Lee, and D. S. Hyun,”A Power-Control Scheme with Constant Switching Frequency in Class-D Inverter for Induction-Heating Jar Application”, IEEE Trans Ind Elec, vol. 54, no. 3, 2007, pp. 1252-1260.

A. L. Shenkman, B. Axelrod and V. Chudnovsky, “A new Simplified Model of the Dynamics of the Current-Fed Parallel Resonant Inverter”, IEEE Trans on Ind Elec, vol.47, no. 2, 2000, pp. 282-286.

E. J. Dade, J. V. Gonzalez, J. A. Linares, J. Jordan, and D. Ramirez, “25kW/50-kHz Generator for Induction Heating”, IEEE Trans on Ind Elec, vol.38, no. 3, 1991, pp. 203-209.

Z. Shu and J. E. Quaicoe, “A PWM Current Source Inverter for Medium-Frequency Induction Heating Applications”, Proc CCECE/CCGEI, 1993, pp. 84-87.

H. javadi and A. Shoulaie, “Analysis of H-bridge Current Source Parallel Resonant Inverter for Induction Heating”, Proc ICEE, 2009, pp. 435-440.

A. Kiyoumarsi, R.-O.-A. Houshmand, R. Ali-Zargar, and M.-r. Hassanzadeh, “Closed Loop Power Control of an Induction Furnace”, Proc ICEMS, 2008, pp. 1-6.

L Hobson, and D. W. Tebb, “Transistorized power supplies for induction”, Int journal on Elec, vol. 59, no. 5, 1985, pp. 543-552.

C. Mu-Ping, C. Jun-Ku, M. Katsuaki, M. Masatoshi, and M. Koosuke, “On the Switching Surge in the Current Resonant Inverter for the Induction Furnace Application”, IEE Japan Trans, vol. 121-D, no. 6, 2001, pp 658-668.

I. Khan, J. Tapson, and I. D. Vries, “Frequency Control of a Current-Fed Inverter for Induction Heating”, Proc ISIE, 2000, pp. 343-346.

R. E. Best, “Phase-Locked Loops : Design Simulation and Applications”, McGraw-Hill, UK, 1999.

A. Carlosena, “Design of High-Order Phase-Lock Loops”, IEEE Trans Cir Sys, vol.54, no.1, 2007, pp. 9-13.

R. W. Wall and H. L. Hess, “Design of Microcontroller Implementation of a Three Phase SCR Power”, Journal of Cir Sys and Comp, vol. 6, no. 6, 1997, pp. 619-63.


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