Maximum power point tracking in solar panels under partial shading condition using equilibration algorithm

Abstract

This paper presents the Maximum Power Point Tracking (MPPT) controller for solving partial shading problems in photovoltaic (PV) systems using Equilibration algorithm. The energy produced by the PV modules depends on the irradiation and temperature. Thus the changing environment creates a necessity to identify the point for every instant on the V-I characteristics of the PV generator in which there is the maximum amount of power transfer from the source to the load. Proper tracking algorithm is required to achieve the maximum power from the PV module. But the performance of a photovoltaic (PV) array is affected by various conditions such as temperature, solar insolation, shading and array configuration. Often the PV array gets shadowed, either completely or partially by passing clouds, neighboring buildings and trees. This situation being the major reason in the case of large PV installations such as distributed power generation scheme and residential PV systems. Under partially shaded conditions, there occurs multiple peaks in the PV curve. Conventional MPPT techniques will not reach the global maximum power point instead it will tend to stay at the local maximum power point which drastically reduces the efficiency of the PV system. This paper provides a elucidation to this problem by executing the equilibration algorithm to identify the global maximum power point (GMPP).