Kii Channel HVDC Link, the ratings of which are 2800MW, 500kV, 2800A in final stage, is constructing to interconnect Sikoku and Kansai electric power systems.
This paper describes the planning of Kii Cannel HVDC Link and new technologies as follows.
·8kV-3500A light triggered thyristors and compact 6tired quadruple thyristor valves.
·500kV DC SF6 gas insulated switchgears.
·Continuous DC operation during AC system faults.

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Recently, it is often observed that the harmonics interference occurs in the AC power line because switching mode inverter and converter have been widely used as power supplies of the electronic and electrical equipment. In order to prevent this harmonics interference, the guideline on the maximum limits of the harmonics distortion factor of the input current was indicated.
In this paper, we propose an electronic ballast with a boosting function that can reduce the harmonics distortion and can work well under 100V of commercial AC power source. The behavior of the circuit is analyzed and experimental results will be shown. The experimental results show that the circuit can decrease the harmonic distortion of the input current. It is revealed that the harmonic distortion of the input current obtained by the proposed electronic ballast satisfies the maximum limit of IEC 1000-3-2 class C sufficiently. And the electronic ballast realized the high power factor of 0.96 and the high efficiency of 0.90.

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A circuit topology for magnetron drive used active clamp quasi-resonant is presented in this paper. A resonant voltage of main switch is clamped for auxiliary switch and capacitor connected at main switch in series. One of advantage of the circuit is operation for PWM output power control under fixed frequency.
Power control limitation is able to extend by constant frequency PWM power control in a method of using a leakage type transformer with several windings supplies power for a magnetron. The variable power control extent is achieved from 100W to 800W for microwave output power. The paper concentrates subject on basic operation and characteristic of cathode current with the output control.

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The demand of low noise level of the washing machine has become high for several years. We judged that it is difficult to respond to this demand, in the conventional deceleration mechanism that used a gear, belt. To achieve “realization of low noise” and “improvement of the fundamental washing performance” simultaneously we developed the high torque direct drive motor, inverter and the torque transmission mechanism that drive a pulsator and washing tub directly. The DD motor that was developed is 3 phase brush-less DC motor. The rotor of this motor is making the multi-pole structure that raised magnetic intensity from a conventional motor, to be satisfied the performance of both “high torque” and “low noise”. Also, the torque ripple that is the cause of noise was able to reduce it, by adopting a sine wave drive PWM inverter system. We describe the outline of the DD motor and inverter system that applied to this washing machine in this paper.

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We propose a simple and an inexpensive wind power generating system in this paper. Existing wind power generating systems are mostly of large capacity (over 100kW) and high-priced (about 700kyen/kW). We adopt compact permanent magnet type synchronous generator, which doesn't need exciting current, and step-up/down buck-boost chopper to wind power generating system of a few kW output without position or speed sensor. In addition, we employ inexpensive rectifier circuit using Diode Bridge instead of AC/DC converter with PWM method. Using this method we achieve a simple and inexpensive wind power generating system.

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High-frequency AC link DC-DC converter with phase-shifted PWM-control scheme apllied soft-switching thecnique have remarkable advantage such as lowered switching losses of power semiconductor device, reduced EMI noise, simple control scheme and so on.
However, The conventional scheme include some inherent problems which must be solved such as reduced power conversion efficiency due to significant circulating current generation.
So we presents before a novel high-frequency AC link DC-DC converter with secondary phase-shifted PWM-control scheme using active switches in rectifier circuit.
In this paper, its operating principle and unique features are described as compered with the simulated analytical and experiment results.

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We have proposed to utilize multilevel converter configuration to reduce higher harmonics and switching loss by keeping the switching frequency at the fundamental frequency. However, voltage control of do side capacitor is difficult for multilevel converter, therefore we have proposed double converter configuration to solve the problem. We have investigated five level converter as an example of multilevel converters, and show its validity. In this paper we discuss the method of reactive power control comparing two methods, phase angle control and pulse width control.

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It is reported that Buck-Boost type SMR can be controlled by only the software without triangle-wave modulation circuit. The DSP is used to generate two sets of the PWM pulse patterns. One is used for the starting of SMR and the other is for the steady state operation, which are both stored in ROM region of the control program. The experimental data show both no harmful rush-current at switch-on and the quick response at steady state operation.

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In recent years, the size of PC servers is getting more compact. The users of the PC server require also downsizing of UPS. It is one of available methods to cut the number of batteries inside it. But for that, we must improve the performance of a boost converter which is driven at discharging. This paper describes compact size new type UPS which is developed by clearing the problem above.

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