Reactive Power Management for Overvoltage Prevention at High PV Penetration in a Low-Voltage Distribution System

A new approach for reactive power management with volt-var control, but considering inverters' capacity and sensitivity to the critical bus is presented in this paper. The approach addresses the voltage rise and reverse power flow issues when residential renewable energy sources such as rooftop solar panels produce more energy than the local load demand. The overvoltage is controlled by selective var injection based on the inverter location, capacity, and minimum power factor limit set by regulation. This method improves the voltage regulation of a distributed system with high penetration of renewable energy sources while efficiently utilizing the inverters' reactive power capacity. Simulation results are presented with a ten inverter network supplied by a 60 kVA distribution transformer. Experimental results are presented to validate the effectiveness of this method for overvoltage prevention of a distribution test system with three photovoltaic (PV) inverters.