Smart loads for voltage control in distribution networks

Summary form only given. This paper shows that the smart loads could be effective in mitigating voltage problems caused by photovoltaic (PV) generation and electric vehicle (EV) charging in low voltage (LV) distribution networks. Limitations of the previously reported smart load configuration with only series reactive compensator (SLQ) (one converter) is highlighted in this paper. To overcome these limitations, an additional shunt converter is used in back-to-back (B2B) configuration to support the active power exchanged by the series converter, which increases the flexibility of the smart load without requiring any energy storage. Simulation results on a typical UK LV distribution network are presented to compare the effectiveness of a smart load with B2B converters (SLBC) against an SLQ in tackling under- and over-voltage problems caused by EVs or PV. It is shown that SLBCs can regulate the mains voltage more effectively than SLQs especially, under over-voltage condition. Although two converters are required for each SLBC, it is shown that the apparent power capacity of each converter is required to be significantly less than that of an equivalent SLQ.