Soon Kurl Kwon

Commercial Frequency AC to High Frequency AC Converter With Boost-Active Clamp Bridge Single Stage ZVS-PWM Inverter

This paper presents a novel soft-switching pulsewidth modulation (PWM) utility frequency ac to high frequency (HF) ac power conversion circuit incorporating boost-active clamp single stage inverter topology. This power converter is more suitable and acceptable for cost effective HF consumer induction heating applications. Its operating principle is presented using the switching mode equivalent circuits in addition to the operating voltage and current waveforms. The operating performances of this high frequency inverter using the latest insulated gate bipolar transistors are illustrated, which includes HFAC power regulation ranges and actual efficiency characteristics based on zero voltage soft switching operation ranges and the power dissipation loss analysis as compared with those of the previously developed high frequency inverter. In addition, a dual mode selected control scheme of this high frequency inverter based on a constant frequency asymmetrical PWM and pulse density modulation control scheme is discussed in this paper in order to extend the soft switching operation ranges and to improve the power conversion efficiency at the low power settings. The practical effectiveness of this power frequency converter is substantially proved on the basis of experimental results from practical design example.

Three-level phase-shift ZVS-PWM DC-DC converter with high frequency transformer for high performance arc welding machines

This paper is concerned with some experimental results and practical evaluations of a three-level phase shifted ZVS-PWM DC-DC converter with neutral point clamping diodes and flying capacitor for a variety of gas metal arc welding machines. This new DC-DC converter suitable for high power applications is implemented by modifying the high-frequency-linked half bridge soft switching PWM DC-DC converter with two active edge resonant cells (AERCs) in high side and low side DC rails, which is previously-developed put into practice by the authors. The operating principle of the three-level phase-shift ZVS-PWM DC-DC converter and its experimental and simulation results including power regulation characteristics vs. phase-shifted angle and power conversion efficiency characteristics in addition to power loss analysis are illustrated and evaluated comparatively from a practical point of view, along with the remarkable advantageous features as compared with previously-developed one.

A New Phase Shifted ZVS-PWM Controlled Full Bridge Series Resonant High Frequency Inverter with Auxiliary Active Quasi-Resonant Commutation Circuit

This paper presents a novel phase shifted ZVS-PWM high frequency load resonant inverter for electromagnetic induction fluid heating (IH) appliances. The proposed high frequency inverter can be achieved stable and efficient zero voltage soft commutation over a widely specified power regulation range from full power to low power by using an active auxiliary quasi resonant snubber. The steady state operating performance of this inverter is evaluated and discussed on the basis of simulation and experimental results for IH dual-packs heater (DPH) of compact fluid heating appliance. Finally, the effectiveness of IH application of the proposed high frequency inverter with auxiliary active quasi-resonant snubber is demonstrated from the practical point of view.

Active voltage clamped edge-resonant soft switching PWM high frequency cyclo-converter using bidirectional switches

This paper presents a utility frequency AC (UFAC) to high frequency AC (HFAC) direct power frequency conversion pulse modulated conditioning circuit using bidirectional power switches. This power converter can efficiently operate under a principle of active zero voltage clamped soft commutation for consumer induction heating (IH) fixing roller for copy machine and printer. This HFAC direct power frequency converter defined as resonant high frequency PWM controlled power frequency converter using bidirectional switches is developed and evaluated in this paper for consumer IH fixing heat roller using industrial HFAC power supply. Its operating principle is described on the basis of switching mode equivalent circuits during switching one cycle period. It is evaluated on the basis of its simulation and experimental results on the performances of HFAC direct power frequency converter treated here including various duty factor control variable vs. HFAC power regulation characteristics as well as zero voltage soft switching ranges.

New Built-In Induction Heating Cooker Using High-Frequency ZVS-PWM Converter with Single Stage Circuit Topology

This paper presents a novel soft-switching PWM utility frequency AC to high frequency (HF) AC power conversion circuit incorporating boost-active clamp single stage inverter topology. This power converter is more suitable and acceptable for cost effective HF consumer induction heating (IH) applications. Its operating principle and the operation modes are presented using the switching mode equivalent circuits in addition to the operating voltage and current waveforms. The operating performances of this high frequency inverter using the latest IGBTs are illustrated, which includes HFAC power regulation ranges and actual efficiency characteristics based on zero voltage soft switching (ZVS) operation ranges and the power dissipation analysis as compared with those of the previously developed high frequency inverter. In addition, a dual mode selected control scheme of this high frequency inverter based on a constant frequency asymmetrical pulse width modulation (PWM) and pulse density modulation (PDM) control scheme is discussed in this paper in order to extend the soft switching operation ranges and to improve the power conversion efficiency at the low power settings. This power frequency converter practical effectiveness is substantially proved on the basis of experimental results from practical design example.

Pulse Width and Pulse Frequency Modulation Pattern Controlled Active Clamp ZVS Inverter Link AC-DC Power Converter Utility AC Side Active Power Filtering Function for Consumer Magnetron Driver

The grid voltage of commercial utility power source in Japan and USA is 100 rms, but in China and European countries, it is 200 Vrms. In recent years, in Japan 200 Vrms out putted single phase three wire system begins to be used for high power applications. In 100 Vrms utility AC power applications and systems, an active voltage clamped quasi-resonant inverter circuit topology using IGBTs has been effectively used so far for the consumer microwave oven. In this paper, presented is a half bridge type voltage-clamped high-frequency inverter type AC-DC converter using which is designed for consumer magnetron drive used as the consumer microwave oven in 200 V utility AC power system. This zero voltage soft switching inverter can use the same power rated switching semiconductor devices and three-winding high frequency transformer as those of the active voltage clamped quasi-resonant inverter using the IGBTs that has already been used for 100 Vrms utility AC power source. The operating performances of the voltage source single ended push pull type inverter are evaluated and discussed for consumer microwave oven. The harmonic line current components in the utility AC power side of the AC-DC power converter operating at ZVS-PWM strategy reduced and improved on the basis of sine wave like pulse frequency modulation and sine wave like pulse width modulation for the utility AC voltage source.

Utility AC Frequency to High Frequency AC Power Converter with Boost-Half Bridge Single Stage Circuit Topology

This paper presents a novel soft-switching PWM utility frequency AC to high frequency (HF) AC power conversion circuit incorporating boost-active clamp single stage inverter topology. This power converter is more suitable and acceptable for cost effective HF consumer induction heating (IH) applications. Its operating principle and the operation modes are presented using the switching mode equivalent circuits in addition to the operating voltage and current waveforms. The operating performances of this high frequency inverter using the latest IGBTs are illustrated, which includes HFAC power regulation ranges and actual efficiency characteristics based on zero voltage soft switching (ZVS) operation ranges and the power dissipation analysis as compared with those of the previously developed high frequency inverter. In addition, a dual mode selected control scheme of this high frequency inverter based on a constant frequency asymmetrical pulse width modulation (PWM) and pulse density modulation (PDM) control scheme is discussed in this paper in order to extend the soft switching operation ranges and to improve the power conversion efficiency at the low power settings. This power frequency converter practical effectiveness is substantially proved on the basis of experimental results from practical design example.

Latest development of transformer parasitic parameters and lossless inductive snubber-assisted ZCS-PFM DC-DC converter for microwave power generation

The conventional series-resonant power frequency modulated DC-DC converter with a high-frequency high-voltage transformer link designed for driving the magnetron of microwave ovens has the problem of the hard switching commutation at turn-on and turn-off of the active power switching devices due to the influence of the magnetizing current of the high-frequency transformer. This paper presents a novel prototype of high-frequency transformer parasitic parameters with a lossless inductive snubber and a series resonant capacitor assisted series-resonant zero current switching pulse frequency modulated DC-DC power converter, which is designed for industrial use of high power magnetron for microwave ovens. In order to implement a complete and efficient soft switching commutation, the performance of the new converter topology is practically confirmed and evaluated in the prototype of power microwave generator from a practical point of view.

A Low Noise Peak Delta-Sigma Modulated DC-DC Converter with Utility Frequency AC Rectified Voltage Source

For the purpose of reducing power loss of power converters, switching power converters are generally used. High frequency operating power conversion realizes small size and lightweight converters. And high frequency switching power converters enlarge new application spheres like mobile equipments. As for the switching power converters, pulse width modulation (PWM) method is generally used. But in case of applying PWM method, switching noise peaks arises on the multiple number of the carrier frequency, and this induces difficulty on clearing noise regulations. To reduce switching noise peaks, delta-sigma modulation scheme has been proposed. But when applying this pulse modulation method for dc-dc converters, switching noise peaks appear like a PWM converter. By the way, dc-dc converters with ac rectified input power source are widely used. Focusing rectified voltage input type dc-dc converter, this paper presents a low noise peak delta-sigma modulated power converter. This proposed converter improves delta-sigma modulation circuit. And it is confirmed that the proposed converter can alleviate switching noise peaks and also effectively suppresses ac rectified ripple component at the dc output side.

Latest Development of Transformer Parasitic Inductive Components and Lossless Inductive Snubber-Assisted Series Resonant High-Frequency ZCS-PFM DC-DC Converter for RF Generator

The conventional series-resonant power frequency modulated DC-DC converter with a high-frequency (HF) transformer link designed for driving the magnetron of microwave ovens has the problem of the hard switching commutation at turn-on and turn-off the active power switching devices due to the influence of the magnetizing current of the high-frequency transformer. This paper presents a novel prototype of high-frequency transformer parasitic parameters with a lossless inductive snubber and a series resonant capacitor assisted series- resonant zero current switching pulse frequency modulated DC-DC power converter, which is designed for industrial use of high power magnetron for microwave ovens. In order to implement a complete and efficient soft switching commutation, the performance of the new converter topology is practically confirmed and evaluated in the prototype of power microwave generator for plasma application from practical point of view.