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Operation of a Medium Voltage Distribution Network with a Large Penetration of Distributed Generation

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The paper presents the study of the behaviour of a real MV public distribution network in a mid-size in Italy, characterized by a very large amount of distributed generation (DG), reaching 100% of supplied network load. A parametric steady-state analysis of operating regimes was carried out, considering different load and DG scenarios (maximum and minimum load, maximum and minimum DG). The deterministic study did not evidence any operational problem, such as overloads and violation of voltage constraints. Occasional voltage violations (high MV voltages at full DG output) are easily overcome by tap-changer operation on the HV/MV transformers. Although feeder voltage profiles are actually improved by DG, a drastic power factor reduction is found at the utility supply points, as well as the possible active power flow inversion, entailing contractual and regulatory issues. Extensive short-circuit studies were also carried out, showing that DG fault contribution in the studied network is far from negligible, but does not dictate changes of either circuit breaker rating or overcurrent relaying coordination.
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Distributed Generation; Active MV Network; Voltage Profiles; Relaying Coordination; Reactive Power

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Autorità per l'energia elettrica il gas e il sistema idrico (AEEGSI), Monitoraggio dello sviluppo degli impianti di generazione distribuita per l'anno 2014, Report available on line (in Italian):

A. Prudenzi, A. Silvestri, M.C. Falvo, R. Lamedica, M. Regoli, A domestic electric load simulator including psychological aspects of demand, IEEE PES General Meeting, Minneapolis, MN, United States, July 2010.

G. Graditi, M.G. Ippolito, R. Lamedica, A. Piccolo, A. Ruvio, E. Santini, P. Siano, G.Zizzo, Innovative control logics for a rational utilization of electric loads and air-conditioning systems in a residential building, Energy and Buildings, Vol. 102:1-17, June 2015.

U. Grasselli, R.Lamedica, A. Ruvio, D. Novati “Management policies for residential and tertiary users: A measurement campaign” International Symposium on Power Electronics Electrical Drives Automation and Motion (SPEEDAM 2014), Ischia, Italy, June 2014.

M. Cresta, F. M. Gatta, A. Geri, L. Landolfi, S. Lauria, M. Maccioni, M. Paulucci, Active distribution networks: MV voltage profiles and loading limits for a large penetration of renewable GD, Proceedings of CIGRE International Symposium 2011, Bologna, Italy, September 2011.

M. Cresta, F. M. Gatta, A. Geri, M. Maccioni, A. Mantineo, M. Paulucci, Reactive power control strategy for voltage regulation and power-factor correction in MV distribution networks, Proceedings of IEEE PowerTech 2015, Eindhoven, Netherlands, June-July 2015.

G.A. Quiroga, H. Kagan, J.C.C. Amasifen, C.F.M. Almeida, E. Vicentini, Evaluation of distributed generation impacts on distribution networks under different penetration scenarios, IEEE PES Innovative Smart Grid Technologies Latin America (ISGT LATAM 2015), Montevideo, Uruguay, October 2015.

P. Pena, N. Morales, M. Artenstein, A. Pizzini, C. Zoppolo, Planning in transmission systems with a great level of penetration of distributed generation, IEEE PES Innovative Smart Grid Technologies Latin America (ISGT LATAM 2015), Montevideo, Uruguay, October 2015.

G. Celli, E. Ghiani, S. Mocci, F. Pilo, Multi-objective programming to maximize the penetration of distributed generation in distribution networks, 20th International Conference on Electricity Distribution (CIRED 2009), Prague, Czechoslovakia, June 2009.

W. Sheng, S. Zhao, X. Song, X. Meng, Maximum penetration level of distributed generation in consideration of voltage fluctuations based on multi-resolution model, IET Generation, Transmission & Distribution, vol. 9(Issue 3):241–248, 2015.

P. Juanuwattanakul, M.A.S. Masoum, Increasing distributed generation penetration in multiphase distribution networks considering grid losses, maximum loading factor and bus voltage limits, IET Generation, Transmission & Distribution, vol. 6(Issue 12):1262–1271, 2012.

F.M. Nuroğlu, A.B. Arsoy, Voltage profile and short circuit analysis in distribution systems with DG, IEEE Electric Power & Energy Conference (EPEC 2008), Vancouver, BC, Canada, October 2008.

G.N. Koutroumpezis, A.S. Safigianni, G.S. Demetzos, J.G. Kendristakis, Investigation of the distributed generation penetration in a medium voltage power distribution network, International Journal of Energy Research, vol. 34(Issue 7):585–593, June 2010.

I. Kim, R.G. Harley, R. Regassa, Y. del Valle, The analysis of voltage increase phenomena in a distribution network with high penetration of distributed generation, IEEE Power Systems Conference (PSC 2015), Clemson, SC, USA, March 2015.

U. Grasselli, R. Lamedica, A. Prudenzi, Time-varying harmonics of single-phase non-linear appliances, Power Engineering Society Winter Meeting, IEEE Vol.2, 2002, pp. 1066 - 1071. DOI:10.1109/PESW.2002.985174

R. Lamedica, G. Maranzano, M. Marzinotto, A. Prudenzi, Power quality disturbances in power supply system of the subway of Rome, IEEE Power Engineering Society General Meeting, Denver, CO, USA, June 2004.

R. Lamedica, M. Marzinotto, A. Prudenzi, Harmonic amplitudes and harmonic phase angles monitored in an electrified subway system during rush-hours traffic, International Conference on Applied Simulation and Modelling (IASTED), Rhodes, Greece, June 2004.

M.C. Falvo, U. Grasselli, R. Lamedica, A. Prudenzi, Harmonics monitoring survey on office LV appliances, 14th International Conference on Harmonics and Quality of Power (ICHQP 2010), Bergamo, Italy, September 2010.

F. M. Gatta, A. Geri, R. Lamedica, M. Maccioni, A. Ruvio, PQ and hosting capacity issues for EV charging systems penetration in real MV/LV networks, Proceedings of Power System Computation Conference (PSCC 2016), Genoa, Italy, June 2016.

M. Cresta, F. M. Gatta, A. Geri, L. Landolfi, S. Lauria, M. Maccioni, M. Paulucci, M. Pompili, Prospective installation of EV charging points in a real LV network: two case studies, IEEE Energy Conference & Exhibition (ENERGYCON 2012), Florence, Italy, September 2012.

A. Bhowmik, A. Maitra, S. M. Halpin, J. E. Schatz, Determination of Allowable Penetration Levels of Distributed Generation Resources Based on Harmonic Limit Considerations, IEEE Transaction on Power Delivery, vol. 18(Issue 2):619–624, April 2003.

F. Coffele, C. Booth, G. Burt, C. McTaggart, T. Spearing, Detailed analysis of the impact of distributed generation and active network management on network protection systems, 21th International Conference on Electricity Distribution (CIRED 2011), Frankfurt, Germany, June 2011.

R. Sinha, A. Zaidi, Protection of distribution systems with significant penetration of distributed generation, IEEE Power Generation System and Renewable Energy Technologies (PGSRET 2015), Islamabad, Pakistan, June 2015.

Autorità per l'energia elettrica il gas e il sistema idrico (AEEGSI), Progetto pilota Smart grid, Report available on line (in Italian):

CYME 5.0 Reference Manual, CYME International T&D Inc., Nov. 2009.

Standard ENEL DK 4452, Guidelines for MV Protective Relay Settings, (in Italian), 2nd Ed., October 2002.


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