A Stand-Alone Sine-Wave Inverter with Reduced Switching Loss

Abstract

Sine pulse width modulation is one technology used mostly in power inverters nowadays to reduce bulky filter requirements and give a pure sinusoidal wave. This paper brings forward a novel stand-alone sine-wave inverter utilizing sine PWM technology in a full-bridge inverter with a modified topology having two additional buck switches connected at the output of a conventional H-bridge topology. This inverter totally deals with six switches from which the two additional switches are the only ones operating at high frequency while the other switches operate at the low (line) frequency. This improves the voltage control and improves the overall efficiency by reducing switching loss. The above topology aims to reduce the switching losses by half as compared to a standard H-bridge hence increasing the efficiency as well as increasing the reliability of the high switching switches as they operate alternatively for only half cycle. The entire idea was simulated and verification of the same was done in laboratory utilizing a prototype model.