Improved Interleaved Single-Ended Primary Inductor-Converter for Single-Phase Grid-Connected System

Abstract

The generation of electricity based on renewable energy sources, particularly Photovoltaic (PV) system has been greatly increased and it is simply instigated for both domestic and commercial uses. The power generated from the PV system is erratic and hence there is a need for an efficient converter to perform the extraction of maximum power. An improved interleaved Single-ended Primary Inductor-Converter (SEPIC) converter is employed in proposed work to extricate most of power from renewable source. This proposed converter minimizes ripples, reduces electromagnetic interference due to filter elements and the continuous input current improves the power output of PV panel. A Crow Search Algorithm (CSA) based Proportional Integral (PI) controller is utilized for controlling the converter switches effectively by optimizing the parameters of PI controller. The optimized PI controller reduces ripples present in Direct Current (DC) voltage, maintains constant voltage at proposed converter output and reduces overshoots with minimum settling and rise time. This voltage is given to single phase grid via 1È Voltage Source Inverter (VSI). The command pulses of 1È VSI are produced by simple PI controller. The response of the proposed converter is thus improved with less input current. After implementing CSA based PI the efficiency of proposed converter obtained is 96% and the Total Harmonic Distortion (THD) is found to be 2:4%. The dynamics and closed loop operation is designed and modeled using MATLAB Simulink tool and its behavior is performed.