The various power quality (PQ) issues in a grid connected solar system arises because of intermittent nature of solar and uncertain loads at the consumer end. The reasons of uncertainties are; nonlinearity, disturbances or unbalanced loads. A three-phase grid-integrated solar photovoltaic (GISPV) system incorporating a control technique based on a modified partial integral (PI) based inverter control algorithm. The controller is so designed so as to obtain the streamline overall performance of the GISPV under adverse conditions.