A NOVEL ZVS-PWM QUASI-RESONANT INVERTER WITH ACTIVE VOLTAGE-CLAMPED CAPACITOR FOR HIGH-FREQUENCY INDUCTION-HEATED APPLIANCE

This paper describes an advanced prototype of voltage-fed zero voltage soft-switching PWM resonant inverter with an active voltage clamped capacitor, which is put into practice for high-frequency high-power induction-heated appliances This application-specific quasi-resonant inverter using the latest generation IGBTs for soft-switching can regulate its output power under a principle of a fixed frequency ZVS-PWM strategy. Its operating principle and unique features are presented as compared with a conventional quasi-resonant ZVS inverter for induction-heated cooker, together with its power regulation characteristics on the basis of its simulation and experimental results. The steady-state performances of this inverter developed for mutli-bumer type induction-heated food cooking appliance are evaluated and discussed from a practical point of view.