Control Strategy for Active and Reactive Power Regulation of Grid Tied Photovoltaic System

A control methodology is presented here to generate and support active as well as reactive power flow from the photovoltaic (PV) system. This system ensures maximum active power extraction from PV system for the load and reactive power support for the grid. Two-stage method is applied for better utilization of PV system. In first stage, DC/DC boost converter is considered and the Perturb and Observe (P & O) algorithm plays important role in extracting maximum power from PV system. In second stage, a power controller is implemented for conversion of DC power to AC power. A current controller along with a dc-link voltage regulator acts as active power controller and current controller along with a sensing unit which senses the quadrature component of the load current acts as a reactive power controller. Active power and reactive power along with voltage and current at different stages of the system have been observed. The system efficiency is found to be approximately 97%.