Micro-inverter with Fuzzy logic based MPPT of Partially shaded PV modules and energy recovery scheme

Abstract

When there is occurrence of partial shading on PV modules there are two to three bypass diodes connected in junction box for 200W rated PV module. Due to this configuration the power-voltage characteristics of the PV module will have many peaks. So to extract maximum power even during the partial shading condition this paper proposes the use of micro-inverter based on flyback configuration with Fuzzy logic based maximum power point tracking technique. This can be achieved by implementing an equalization circuit across the PV module. This equalization circuit consists of series connection of diode and secondary winding of the flyback transformer of the micro-inverter. This equalization circuit is capable of energy recovery from the leakage inductance of the converter when the main switch is turned off. This proposed topology have the following features: fuzzy logic based mppt to extract maximum available power, energy recovery capability and conversion of dc to ac. The proposed technology’s effectiveness is analyzed by comparing it with PV module having bypass diode configuration. The simulation results, control strategies and modes of operation and analysis of the proposed topology are presented in this paper.