High-frequency induction heating inverter with multi-resonant mode using newly developed normally-off type static induction transistor

This paper is mainly concerned with the state-of-the-art developments of the voltage-fed voltage-clamped type half-bridge topology of a new instantaneous resonant current vector-regulated high-frequency inverter, which efficiently operates at zero-current soft-switched quasi-resonant and load resonant tank circuit sub-resonant hybrid soft-switching schemes. This proposed multi-resonant inverter version using newly-developed high-frequency high-power normally-off type bipolar mode static induction transistors (B-SITs) is more suitable for a modern induction-heating and -melting power supply in industrial production plants. Its new conceptional operating principle is basically presented, including the control strategy, and its remarkable features are discussed. Its analytical results and performance evaluations are described through computer-aided simulation methods. A feasible breadboard of a trial inverter is originally demonstrated for the state-of-the-art induction heating power supply and is examined in an experiment from a practical point of view