Switching Method of Step-down Chopper for DC Inductor Volt-second Balance in Single-phase PWM Current Source Inverter-PV Generation System

Abstract

This paper presents a switching method of step-down chopper in single-phase current source inverter for photovoltaic generation. The on and off times of the chopper switch depend on the inverter PWM operation and the utility voltage, and these are determined by utilizing per carrier cycle volt-second balance for the dc inductor. The experimental result proves that the proposed strategy achieves the smoothing dc current and allows the dc reactor to be greatly reduced.