Eliminating The Problem of Trapping in Local Maximum Power Point under Partial Shading Conditions for PV System

Abstract

This study realizes a new solar-power generation system that can complete the global maximum power point tracking (GMPPT) control under uniform irradiation and partial shading conditions (UIC and PSC, respectively). The MCU of the proposed system calculates the IGMPP of the photovoltaic (PV) module to accurately execute GMPPT on the basis of the PV module current (Ipv), power (Ppv) and temperature trend line slope (dIpv/dPpv). The microcontroller unit can then confirm whether the PV module suffers from shading according to the slope (dIpv/dPpv) and immediately executes the PSC mode control strategy to calculate the VGMPP of the PV module, thereby accurately tracking the GMPP. The proposed algorithm is compared with the existing methods. Such model is then practically experimented from the irradiance levels of 1000 W/m2 and under PSC. Experimental results confirm that the performance of the algorithm is better than those of the traditional hill-climbing algorithm and perturbation and observation methods.