Grid connected single phase rooftop PV system with limited reactive power supply

Abstract

Photovoltaic (PV) systems proposes attractive alternative source of generation because these can be placed near to the load centers when compared with other renewable source of generation. It is therefore rooftop PV is the centre of attraction for majority PV systems. The rooftop PV system in general is grid connected and supports the off grid load with battery backup. The designed system must ensure total evacuation of generated power and with high efficiency of conversion, and utilizes the resource adequately to maximize the utilization of energy. This paper proposes single phase synchronous reference frame (SRF) theory based current controlled PWM controller for the voltage source converter (VSC) to realize maximum generated power evacuation by maintaining the DC link voltage constant without battery support, low THD sinusoidal line synchronized current output, and limited reactive power compensation based on the unutilized capacity of the inverter. PV power is being tracked always at MPP through incremental conductance (IC) method. MATLAB based simulation results shows the efficient working of rooftop PV with proposed control algorithms in grid connected mode with limited reactive power conditioning.