An Auxiliary Switch Commutated ZVS Boost Converter with Coupled Inductor

This paper presents a novel soft switching circuit for the boost converter. This is done through an additional auxiliary switch and a resonant circuit. It provides zero voltage switching for the main switch and zero current switching for the auxiliary switch. The paper presents the idealized analysis giving all the circuit intervals and the equations necessary to design such a circuit. The proposed soft switching circuit is particularly suited for the tapped inductor boost circuit. Extension of the method to tapped inductor boost converter addresses the application of zero voltage transition to high conversion ratio converters. A laboratory prototype boost converter rated 125 W; 24 V input confirms the theoretical results and design methods. Both simulation and experimental results show that soft switching can be achieved for a wide line and load range.