Switched Capacitor Snubber-Assisted Zero Current Soft Switching PWM High Frequency Inverter with Two-Lossless Inductive Snubbers

In this paper, a novel type of auxiliary switched capacitor assisted edge resonant soft switching PWM series load resonant high frequency inverter with two auxiliary edge resonant lossless inductor snubbers is proposed for small consumer induction heating appliances. The operation principle of this high frequency inverter is described using the switching mode equivalent circuits. This newly developed multi resonant high frequency inverter using trench gate IGBTs can regulate its high frequency output AC power under a principle of constant frequency edge-resonant soft switching commutation by asymmetrical PWM control scheme. The high frequency power regulation and actual power conversion efficiency characteristics of consumer brand-new IH products that use the proposed soft switching PWM series load resonant high frequency inverter are evaluated. The practical effectiveness and operating performances of the newly proposed soft switching inverter are discussed as compared with the conventional soft switching high frequency inverters based on simulation and experimental results from an application point of view.