Shinichiro Sumiyoshi

Power Conditioner Consisting of Utility Interactive Inverter and Soft-Switching DC-DC Converter for Fuel-Cell Cogeneration System

Renewable energy has been a great concern to obtain ecological society that can continuously grow. As an hopeful solution, the fuel cell cogeneration system has been attracted and some first products have been developed in Japan and in some other centuries/areas. A product in Japan, which is the first developed system and hundreds of the sets are under operation in homes, has been investigated The novel topology consisting of a high-frequency transformer isolated soft-switching DC-DC converter and a utility interactive PWM inverter is practically evaluated.

Latest practical developments of triplex series load resonant frequency-operated high frequency inverter for induction-heated low resistivity metallic appliances in consumer built-in cooktops

This paper deals with the new generation prototype of one-stage boost-half bridge (B-HB) series load resonant softswitching high-frequency inverter with a lossless snubbing edge resonant capacitor and two selective resonant capacitors in series with inductive load for consumer induction heating (IH) appliances. The B-HB high frequency inverter treated here is based upon a dual series load resonant frequency selection strategy, changed automatically in accordance with resistivity of metallic materials as IH loads. In the first place, the triplex series load resonant high frequency (three times of switching frequency) operated B-HB inverter is demonstrated for IH non-magnetic low resistivity metallic pans/utensils fabricated by aluminum, copper and multi-layer of aluminum and stainless steel. In the second place, the fundamental series load resonant frequency (switching frequency) operated B-HB high frequency inverter is also described for IH magnetic high resistivity metallic pans/utensils fabricated by iron, iron cast and stainless steel. Finally, the principle of operation and inherent unique features of the B-HB high frequency inverter employing dual series load resonant frequency selection scheme in accordance with either low resistivity or high resistivity IH loads is presented from an experimental point of view, along with its operating steady state performance. This new generation B-HB frequency inverter type built-in IH cooktop with two/three ranges is put into practice for home energy utilizations in all electricity residential systems.

Utility-interactive solar power conditioner using high-frequency sinewave modulated inverter for distributed small-scale power supply

The utility interactive sinewave soft commutation inverter using IGBTs for solar photovoltaic power conditioner with a high frequency transformer is presented for residential applications. As compared with the conventional full-bridge hard switching sinewave PWM inverter with a high frequency link, the simplest single-ended quasi-resonant soft switching sinewave inverter with a sinewave duty cycle control scheme is developed, resulting in size and weight reduction, low-cost and efficiency. This paper presents a prototype system of the sinewave ZVS-PWM inverter for solar power generator, along with its operating principle and unique features. In addition to these, this paper discusses a control implementation to deliver high quality output current to be injected into the utility 1φ AC. The power loss analysis under actual power conditioning and processing is also discussed and evaluated from an experimental point of view. A compact utility-interactive sinewave power conditioning circuit which achieves 92.5% efficiency under 4 kW output is demonstrated.

4H-SiC-DIMOSFET power device for home appliances

The 5×4.2 mm2 chip of the SiC DIMOSFET was fabricated and tested. The drain-source avalanche breakdown voltage without any gate bias (Vgs=3D0V) is measured to be >1000V. The drain current (Id) >40A is observe under the conditions of Vds=3D1V and Vgs=3D+20V. Typical Ron and specific Ron are measured to be 22 mΩ and 3.5 mΩcm2 with V<inf>th</inf>=3D2.3V. The SiC DIMOSFET is introduced into the PE circuits of the commercially available all-metal IH cooktop to test the loss-energy saving. On the PFC circuit, 2/3 reduction of the energy loss of the SW device is confirmed. On the inverter circuit, 21W reduction of the energy loss of the SW device is confirmed.

A single stage induction heating high frequency series load resonant ZVS-PWM inverter with active filtering pfc rectifier operating at one diode conduction and ZCS commutation

This paper presents newly developed half bridge ZVS-PWM high frequency inverter using ZCS-PFC converter conducting full bridge 1 diode. This high-frequency inverter is composed of a passive PFC converter operating at one diode conducting bridge circuit and asymmetrical ZVS-PWM high frequency resonant inverter without the bulky electrolytic capacitor stage for boosted DC voltage smoothing. In addition, this proposed high-frequency resonant inverter has only one diode conducting mode in the diode bridge rectifier with boost inductor. The operating principle of the proposed series load resonant high frequency inverter is described by using the switching mode equivalent circuits in addition to the simulated operating voltage and current waveforms. The circuit parameters of proposed high frequency inverter design to achieve one diode conduction at the same time at diode bridge part by simulation analysis in this paper. The operating performances of this proposed ZVS-PWM high-frequency inverter are also 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.

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.

A novel one stage ZVS-PWM high frequency resonant inverter with boost single diode conducting mode passive ZCS-PFC scheme

This paper presents a high-efficiency one stage ZVS-PWM resonant single-ended push-pull (SEPP) high frequency inverter with new PFC functional scheme. This high-frequency resonant power converter with lossless snubbing capacitors which is composed of a passive PFC converter operating at one diode conducting full bridge circuit mode consists of asymmetrical ZVS-PWM high frequency inverter with non-bulky electrolytic capacitor stage for DC boosted voltage smoothing and induction heated load with tuned capacitor, and boost inductor between HFAC side and mid point of. The periodic steady-state operating principle of one stage high frequency series load resonant inverter with lossless capacitor 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 inverter with lossless snubbing capacitors are also 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 line current harmonics characteristics by FFT analysis. In principle, the effectiveness of this UFAC-to-HFAC direct power frequency converter designed for consumer high-frequency III appliances is evaluated and proved on the basis of simulation results.

High-Frequency Transformer Isolated Soft-Switching DC-DC Converter for Fuel Cell Cogeneration System

A high-frequency transformer isolated soft-switching DC-DC converter for fuel-cell cogeneration systems with utility-interactive inverter is investigated. The new type DC-DC converter offers a high efficiency in a wide power range, from rated to low power, by means of a new soft-switching topology. A prototype of the DC-DC converter and utility-interactive inverter cascade system is practically evaluated to confirm the fine performance

Dual PWM controlled soft switching high frequency IH load resonant inverter with lossless snubbing capacitor and switched capacitor

This paper presents a prototype of voltage-fed high-frequency IH load resonant inverter with lossless snubbing capacitor and resonant switched, along with its unique features. This high frequency soft commutation resonant inverter using IGBT power modules is developed for consumer induction heated cooking heater, steamer and super heated steamer. The operating principle of the high frequency resonant inverter proposed here in is illustrated my using periodic switching mode equivalent circuit. The voltage and current waveforms are verified through comparative simulation and observed results. Furthermore, the operating performances including high-frequency AC regulation and power conversion efficiency on the basis of dual duty cycle PWM scheme are discussed in experiment. The cost effectiveness of the proposed high frequency resonant soft-switching inverter is verified from a practical point of view.

Integrated power converter for photovoltaic and Fuel Cell systems in home

Renewable energy has been a great concern to obtain ecological society that can continuously grow. As an attractive solution, the fuel cell cogeneration system has been attracted and some first products have been developed in Japan and in some other centuries/areas. A product in Japan, which is the first developed system and few hundreds of the sets are under operation in Japanese homes, has been investigated and practically evaluated in this digest. The novel topology consisting of a high-frequency transformer isolated soft-switching DC-DC converter and a utility interactive PWM inverter are introduced and practically evaluated.