Hidekazu Muraoka

High-frequency PWM forward converter with auxiliary active clamped capacitor for low voltage high current operation

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.

High efficient series resonant high frequency inverter with ZCS-pulse density modulation for copy machine fixing roller in office information and automation applications

This paper presents the two lossless auxiliary inductor assisted voltage source type half bridge series resonant high frequency inverter for induction heated fixing roller in copy and printing machines. This high-frequency inverter treated here can completely achieve stable zero current soft switching (ZCS) commutation for wide power regulation ranges and load variations under its constant frequency pulse density modulation (PDM) scheme. Its transient and steady state operating principle is originally presented for a constant high-frequency PDM control strategy under a ZCS operation commutation, together with its output effective power regulation characteristics-based on the PDM strategy. The experimental operating performances of this voltage source ZCS-PDM high frequency inverter using IGBTs are illustrated as compared with computer simulation ones. Its power losses analysis and actual efficiency are evaluated and discussed on the basis of simulation and experimental results. The effectiveness of this high frequency inverter appliance is proved from the practical point of view.

Dual mode ZVS-PWM high frequency load resonant inverter with auxiliary edge resonant snubber for super heated steamer

In this paper, a dual mode phase-shift PWM full bridge-type series load resonant high frequency inverter is presented for induction heating applications. The bridge arm side passive capacitor snubber and/or AC load side active edge resonant snubber-assisted series load resonant soft switching inverter with a dual mode phase shift PWM scheme is evaluated and discussed on the basis of simulation and experimental results. It is proved from a practical point of view that this new inverter topology can expand soft switching area even under low power setting ranges.

Cost effective soft-switching PWM high frequency inverter with minimum circuit components for consumer induction heater

This paper presents a novel prototype soft-switching PWM high frequency inverter with minimum circuit components, which can achieve the wider and more stable soft commutation, simpler circuit configuration, smaller size, lower cost and higher-efficiency as compared with active voltage clamped ZVS-PWM and single-ended ZVS-PFM high frequency inverters developed previously. This quasiresonant soft-switching PWM high frequency inverter operating under ZVS and ZCS arms-related soft commutation is including the voltage-clamped ZVS-PWM inverter in the constant frequency variable power scheme as well as a single-ended ZVS-PFM inverter. The operation principle of soft switching PWM high frequency inverter treated here is described on the basis of the simulation and experimental results, together with its comparative operating performances in steady state. The practical effectiveness of a novel type high frequency soft-switching PWM inverter using state-of-the-art IGBT power modules is actuary proved for consumer induction heated appliances as cooker, super heated steamer and hot water producer.

Soft-switching PWM-PDM controlled high-frequency link DC power converter operating at battery input

This paper presents a innovative prototype of PWM soft-switching DC-DC forward type converter designed for specific low voltage large current condition at 24 V battery input. To achieve soft-switching, prototype of ZCS PWM DC-DC forward type converter applies additional control mode at partial operating area. The proposed converter is controlled by dual modulation as PWM-PDM at low duty operation. The soft-switching forward converter controlled PWM-PDM dual control scheme which can efficiency operate over wide load ranges under conditions of ZCS and active voltage clamped switching is established.

Electromagnetic induction eddy current-based far infrared rays radiant heater using soft switching PWM inverter with duty cycle control scheme

This paper presents an innovative prototype of a new electromagnetic induction eddy-current heated type far infrared rays radiant heating appliance using the voltage-fed edge-resonant ZVS-PWM high frequency inverter using IGBTs for food cooking and processing. This soft switching inverter can operate under a constant frequency variable power regulation scheme in order to heat the spiral planar induction heater made of the stainless steel plate. This power electronic appliance with soft switching high frequency inverter using IGBTs has attracted special interest from some advantageous viewpoints of safety, cleanliness, compactness and rapid temperature response, which is more suitable for consumer power electronics applications.