Over-voltage regulation capability analysis of rooftop photovoltaic grid-connected inverters

The rooftop photovoltaic (PV) is becoming more popular these years for its economical and environmental benefits. Nevertheless, the over-voltage problem on point of common coupling (PCC) often occurs in the rural distribution network because of the PV power and load fluctuations. Aiming at the PCC bus over-voltage in rooftop PV grid-connected system, this paper, focusing on the 10kV distribution network of rural areas, analyzes the over-voltage regulation capability of the PV inverters. Two common models of the rooftop grid-connected PV inverters are established in MATLAB, both the load on grid side and the PV power supply fluctuations are all discussed to analyze the fluctuations of the PCC bus voltage. The experimental results could provide important basis for improving the voltage stability of distribution network, including the optimization of PV inverter control strategy, and the necessity of planning local reactive power compensation device.