PolyGrid – A two-vector energy independent microgrid at

University “Politehnica” of Bucharest

Lucian Toma 1, Dumitru Popescu 2, Mihaela Albu 3, Constantin Bulac 1, Ion Necoara 2

Abstract: With the advent of new technologies running on renewable energy sources (e.g. wind and solar) and small size but highly efficient fossil fuelled power plants (i.e. natural gas and petroleum), the number of distributed generators in the low voltage and medium voltage networks has significantly increased in the last decade and will continue to increase in the near future. The electrical grid of the campus of University POLITEHNCA of Bucharest is connected with the main distribution grid of the Bucharest City through two 10 kV cables from a central substation owned by the university. Since this substation acts as a hub, the electrical grid of the campus can be seen as a microgrid

Index Terms: Microgrid, Distributed Generation, Virtual Power Plant, Controllable Load, Independent Consumer, Active Network, Smart Grid, Educational Platform

1. University “Politehnica” of Bucharest, Faculty of Power Engineering

2. University “Politehnica” of Bucharest, Faculty of Automation and Computer Science

3. University “Politehnica” of Bucharest, Faculty of Electrical Engineering

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Fig. 2 Variaţia puterii generată de o instalaţie fotoelectrică cu puterea nominală

de 30 kWp, pe durata a 25 zile.

Pinst = 30 kW

Eav = 6 kWh/h

CF = 20%

Commissioned: 26 May 2006

Payback time >> Lifetime

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• Lucian Toma, Mircea Eremia, Dorin Bică – Economic operation of distributed energy resources in a microgrid, Proceedings of 2013 IEEE Grenoble

PowerTech, Grenoble, France, 16-20 June 2013. • Mihai Sănduleac, Mircea Eremia, Lucian Toma, Paul Borza – Integrating the Electrical Vehicles in the Smart Grid through Unbundled Smart Metering and

multi-objective Virtual Power Plants, IEEE PES Innovative Smart Grid Technology Europe, ISGT-2011, Manchester, 5-7 December 2011.

• Mihaela Albu, E. Kyriakides, G. Chicco, M. Popa, A. Nechifor -- Online Monitoring of the Power Transfer in a DC Test Grid, IEEE Trans. on Instr. and

Meas., vol. 59 , Issue: 5 , 2010

DC ring @ 230 V, 5 kW laboratory and classroom