A novel type single-stage ZVS-PWM high-frequency load resonant inverter with high performance PFC rectifier for consumer IH appliances

This paper presents a high-efficiency-high power density one stage ZVS-PWM single-ended push-pull (SEPP) high frequency inverter with new PFC functional scheme. This high-frequency resonant series load resonant inverter with lossless snubbing capacitors is composed of a passive PFC converter operating at one diode conducting bridge circuit and asymmetrical ZVS-PWM high frequency resonant direct inverter without the bulky electrolytic capacitor stage for boosted DC voltage smoothing. In addition, this one stage utility frequency AC (UFAC) to high frequency AC (HFAC) conversion circuit has only one diode conducting mode in the diode bridge rectifier with boost inductor. The operating principle of the one stage UFAC to HFAC series load resonant inverter with lossless capacitors is described by using the switching mode equivalent circuits in addition to the simulated operating voltage and current waveforms. The operating performances of this high-frequency ZVS-PWM resonant direct inverter with lossless snubbing capacitors are illustrated on the basis of simulation analysis which includes its UFAC-to-HFAC power regulation characteristics, soft switching operating range, UFAC side power factor characteristics and UFAC side line current harmonics characteristics by FFT analysis. In principle, the effectiveness of this UFAC-to-HFAC direct power frequency converter using IGBTs for consumer high-frequency IH appliances is evaluated and proved on the basis of simulation results.