New integration concept of auxiliary commutation circuits: ZVT case study

This paper proposes the concept of integrated ZVT auxiliary commutation circuits applied to systems with power conversion multi-stages. With this concept, it is possible to reduce the number of additional elements as well as to minimize the circulating reactive energy. A new integrated ZVT auxiliary commutation circuit is applied to a double-conversion UPS to demonstrate the functionality of this new concept. By using this new circuit, the main switches operate under soft-commutation of ZVT type, and the auxiliary switches are turned-on and turned-off under ZCS or ZVS. Experimental results of a 1 kW@100 kHz prototype are presented the feasibility of the proposed concept.