Voltage Compensation Method for Multi-feeder Distribution Networks Based on a UPQC with PV Injection

In response to the problem of prolonged low voltage at the end of distribution grids, a voltage compensation method for multi-feeder distribution networks based on a unified power quality controller (UPQC) with PV injection is proposed in this paper. In the proposed scheme, two series inverters, a single parallel rectifier and photovoltaic (PV) system are flexibly interconnected via DC bus. The voltage attenuation can be compensated by the two series inverter, and the parallel rectifier is capable of supplying energy to the DC side of the two series inverters on adjacent AC feeders. Meanwhile, active power can also be supplied by the PV panel through a DC/DC converter. The operation modes and control strategies of the proposed method are analyzed in-depth. Finally, a MATLAB/Simulink model is shown to verify the effectiveness of the method proposed in this paper.