Photovoltaic grid-connected inverter using two-switch buck-boost converter

Abstract

This paper presents a two-stage photovoltaic grid-connected inverter. The first stage is a two-switch buck-boost circuit that performs various functions; tracking a maximum power point of the photovoltaic array and controlling current using fixed frequency current mode control technique; as well as reforming a direct current waveform to an absolute sinusoidal waveform. The second stage is a H-bridge switch that converts an absolute sinusoidal waveform to a sinusoidal waveform with a low harmonic distortion current and connected to utility. The system configuration is reliable using a single-chip DSP controller. Experimental results satisfy with simulation.