Review of Soft-Switching Topologies for Single-Phase Photovoltaic Inverters

Abstract

Soft-switching is one of the effective techniques to improve the efficiency and power density of power electronics converters. This paper presents a comprehensive review of the soft-switching topologies used in single-phase photovoltaic (PV) inverters for residential applications. The topologies of single-phase PV inverters are investigated and divided into two types of power conversion stages: the PV interface stage boosting PV voltage and the grid interface stage feeding ac power to the utility grid. The soft-switching topologies for each type of power conversion stage are reviewed and compared respectively, including the soft-switching mechanisms, efficiency, device ratings and design challenges. Discussions and recommendations of soft-switching topologies for each stage are also provided. This paper is an attempt to provide a point of reference for the design of high-performance single-phase PV inverters.