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The simple and low-cost operation at zero voltage soft commutation voltage-fed quasi-resonant PFM inverter is widely used, which is more suitable and cost effective for consumer induction heated cooking appliances. This paper presents feasible performance evaluations of each generation IGBT developed and MOS controlled thyristor (MCT) incorporated into the simplest voltage source type quasi-resonant PFM inverter operating in zero voltage soft switching transition mode for induction heated loads. New generation IGBT in addition to MCT have been improved in order to reduce their conduction power losses which are based on their lowered saturation voltage characteristics in addition to high current density. In the first place, each generation IGBT is respectively built and tested on the basis of a single-ended quasi-resonant PFM inverter circuit operating at zero voltage soft switching commutation. In the second place, the power loss-temperature analysis of the latest IGBT with a trench-gate structure is discussed and evaluated from an experimental point of view. In the third place, the further reduced saturation voltage and conduction power loss characteristics of attractive MCT are presented in comparison with the 3rd generation IGBT by using zero voltage high current density soft-switching inverter for consumer high frequency power application.

This paper presents a novel prototype of active voltage-clamping capacitor-assisted soft switching PWM inverter operating at a constant frequency variable power (VPCF) regulation scheme, which is suitable for consumer high-power induction-heating cooking appliances. New generation IGBT with a trench gate is particularly improved in order to reduce conduction loss due to its lower saturation voltage characteristics. The soft switching load resonant and quasiresonant inverter using the latest IGBTs designed specially, is evaluated from an experimental point of view.

This paper presents boost and buck and buck-boost circuit topologies of high-frequency soft switching transition PWM chopper type DC-DC high power converters with a single auxiliary passive resonant snubber. In the proposed boost power converter circuits operating under the principle of ZCS turn-on and ZVS turn-off commutation schemes, the capacitor and inductor in the auxiliary passive resonant circuit works as lossless snubber which is more effective to reduce the DC load side power recovery feedback-based switching losses of active power switch for high frequency switching and control. In addition to this, the switching voltage and current peak stress as well as EMI and RFI noises can be basically reduced by this single passive resonant snubber. Moreover, it is proved that converter topologies with a passive resonant snubber are capable of solving some problems of conventional hard switching PWM processing based on high-frequency pulse modulation principle of operation, the simulation results of this converter are discussed as compared with the experimental ones.

This paper presents a novel prototype of ZCS-PWM forward DC-DC power converter designed for specific low-voltage high-current operation. A soft-switching forward power converter with a high frequency isolated link which can efficiently operate over wide load ranges, under conditions of ZCS and active voltage clamped switching, is established.

An auxiliary resonant commutated snubber-assisted inverter with bidirectional active power switches and voltage clamping diodes is presented in this paper. The voltage clamping diodes protect the bidirectional active switches from spike surge voltage caused by recovery energy of the auxiliary inductors and parasitic wired inductances. Moreover, a variety of resonant snubber-assisted circuits with voltage clamping diodes are also classified and presented from a practical point of view. Finally, the performances of the proposed auxiliary resonant commutated snubber-assisted inverter with voltage clamping diodes is demonstrated and evaluated in order to prove its feasibility applying for X-ray high-voltage generator.