Fast-converging MPPT technique for Photovoltaic system using dsPIC controller

Abstract

Power developed in a Photovoltaic (PV) system is greatly depends on the solar irradiation and the load. There are lot of methods used to track the maximum power point (MPP) under varying solar irradiation. In conventional methods the algorithm require an extra control loop or intermittent disconnection of the PV module to track the MPP, so power dissipation is higher. Here an algorithm is explained to track the MPP under both irradiation and load resistance variation using relationship between load line and MPP locus. Duty cycle of a Single-Ended Primary Inductor Converter (SEPIC) is adjusted to reach the MPP under varying irradiation and load resistance there by convergence speed can be improved. dsPIC controller is used to measure the voltage and current and executes the algorithm.