Development of Control Strategy for Load Sharing in Grid-Connected PV Power System

Abstract

In a power system of conventional parallel connected generators, share of real power and reactive var of an incoming generator are controlled by adjusting shaft power input and field excitation. The scenario of load sharing by a grid connected PV system is however different since no prime mover or excitation source are present. Due to serious power crisis, there are needs for transfer of PV power to grid systems. However, this needs intensive analysis on the load sharing phenomena. In this paper, aspects of load sharing of a grid connected PV system are analyzed, and a strategy is proposed where the load sharing task can be undertaken controlling both modulation index and phase angle of the inverter. It is seen that both real power and reactive var are affected upon change in index of modulation and phase angle of the PV inverter. Analysis and simulation results are presented to demonstrate effectiveness of the proposed control technique.