A single phase T-type inverter operating in boundary conduction mode

This paper proposes a single phase T-type inverter operating in boundary conduction mode (BCM). In the past, boundary conduction mode has been widely used to achieve valley voltage switching. In this paper, one switching leg of a full-bridge inverter is replaced by a T-type switching leg to further improve the efficiency. Because the T-type switching leg generates three voltage levels, the voltage stress across switches is halved and the switching frequency decreases compared with the conventional two-level full-bridge inverter operating in BCM. As a result, the switching losses and inductor core losses are largely reduced and the efficiency is improved. The characteristics of the proposed inverter are detailed in this paper. A prototype is built and experimental results validate the superiority of the proposed inverter over the conventional two-level full-bridge inverter.