A new ZVS phase-shifted high-frequency resonant inverter incorporating asymmetrical PWM-based unit control for induction heating

A novel high-frequency (HF) soft switching resonant inverter for induction heating (IH) applications is presented in this paper. By adopting the phase shift-controlled two-inverter mode and the asymmetrical PWM-based single-inverter mode, the IH load resonant current can be regulated continuously under the full-load range soft switching conditions with maintaining high efficiency. The essential performances on the output power control and soft switching operations are demonstrated in experiments using a 450W-70 kHz prototype, then its topological validity is evaluated from the practical point of view.