Soft-switched PWM high-frequency load-resonant inverter for induction heating cooking appliance

There is a strong demand for high-power multi-burner induction-heating cooking appliances. It is known that acoustic noise can be generated when conventional frequency-controlled inverters are applied to multi-burner IH cooking heaters. In order to eliminate the acoustic noise, this paper presents a prototype type of voltage-fed quasi-load resonant half-bridge inverter operating at constant frequency variable power (CFVP) regulation scheme which is more suitable for new high-frequency high-power IH cooking heater appliances. This application specific high-frequency inverter using a new generation IGBTs can operate under a principle of ZVS-PWM strategy. The operating principle of a new inverter circuit is presented together with its power regulation characteristics on the basis of computer-aided simulation analysis & experimental results. The steady-state characteristics of this quasi-resonant inverter developed for IH cooking heater appliance are discussed herein.