A New Single-Phase Switched-Coupled-Inductor DC-AC Inverter for Photovoltaic Systems

Abstract

This paper presents a new single-phase switched-coupled-inductor DC-AC inverter featuring higher voltage gain than the existing single-phase qZ-source and semi-Z-source inverters. Similar to the single-phase qZ-source and semi-Z-source inverters, the proposed inverter also has common grounds between the DC input and AC output voltages, which is beneficial especially for photovoltaic inverter systems. The inverter volume and maximum current flowing can be reduced significantly through the coupling of all inductors.

Existing System

Push-Pull Switched-Capacitor Luo-Converters.

Proposed System

In this paper, the single-phase switched coupled inductor DC-AC inverter was presented. It has an operation principle similar to that of a single-phase qZ-source inverter. Although higher voltage gain is obtained, the three inductors in the TSTS-ZSI make the circuit a bit bulky and heavy. In addition, the switch signals of the inverter are all different and relatively complicated. 1 L2 L3 L. In this paper, a single-phase switched-coupled-inductor (SCL) dc-ac inverter is proposed. Similar to the TSTS-ZSIs, the proposed inverter maintains same ground between Vin and Vo. The proposed inverter also requires three active switches, but all the inductors in the circuit can be coupled together, which will lead to more compact and cost effective solution than the TSTS-ZSI. In addition, the switch signal generation is relatively simpler than the TSTS-ZSI.

Architecture

Proposed Dc-Ac Inverter