Actively clamped zero-current-switching quasi-resonant converters using IGBTs

Conventional zero-current-switching quasi-resonant power converters (ZCS-QRCs) suffer from the disadvantages of high switch current stress and variable switching frequency. This paper proposes the use of a "current-clamping circuit" to overcome these disadvantages. By incorporating such a circuit into the family of ZCS-QRCs, a new family of actively clamped ZCS-QRCs using insulated gate bipolar transistors (IGBTs) is derived. These power converters feature high (and constant) switching frequency and zero-current turn-off (without increased current stress), which are particularly useful for high-power applications where minority-carrier semiconductor devices (such as IGBTs and bipolar junction transistors) are used as power switches. The design criteria, simulation and experimental results are reported.