Mitsubishi Heavy Industries Limited

Mitsubishi Jukogyo Kabushiki Kaisha

Osamu Kawabata

Koji Nakano

Jun Utsumi

Tetsuro Shigemizu

Yasutoshi Ueda

Kazutaka Tomimatsu

Hisanobu Shinoda

Shunsuke Kamei

Noriyuki Akasaka

Yoshio Kayuki

Mitsuyuki Nonaka

Sakao Sugiura

Nobuo Teramura

A DC/DC converter is comprised of a bipolar transistor, an inductor, a smoothing capacitor, an input terminal, an output terminal, and a grounded terminal. A base of the transistor includes a silicon germanium layer. The bipolar transistor has a high switching speed and a low on-state voltage through an optimization of a structure of the transistor.

DC/DC converter using bipolar transistor, method of manufacturing the same and DC power supply module using the same

A motor driving system for driving an induction motor with a rotation frequency detector. The induction motor drives a load, and the rotation frequency detector detects a rotation frequency of the induction motor. The motor driving system includes a variable speed driving unit and an inverter control unit. The variable speed driving unit is connected to the induction motor and has a capacitance at output. The variable speed driving unit rectifies first 3-phase AC power to produce DC power, and converts the DC power into second 3-phase AC power with a frequency, and drives the induction motor with the second 3-phase AC power. The inverter control unit generates a frequency instruction and a temporary current instruction based on the detected rotation frequency and a rotation frequency instruction at least. Then, the inverter control unit corrects the temporary current instruction based on at least one of first correction depending on a value of the capacitance and second correction depending on a predetermined frequency component of the temporary current instruction to produce a current instruction, and controls the variable speed driving unit based on the frequency instruction and the current instruction.

Inverter control apparatus and motor driving system

A pulse charging apparatus includes a DC high-voltage generator, a capacitor that is charged by a DC high voltage output from the DC high-voltage generator, a switching unit for switching charges stored on the capacitor to provide a pulse-like high voltage to a load, and a control unit for controlling the operation of the switching unit. The switching unit consists of a series combination of an electron tube and a stationary gap. The control unit controls the operation of the electron tube.

Pulse charging apparatus using electron tube for switching control

There is provided a capacitor having an end connected to the ground and the other end connected through a secondary winding of a pulse transformer to the discharge electrode. The ground side terminal of the capacitor is connected through a smoothing circuit to a positive voltage side output terminal of a base power supply circuit and a negative voltage side terminal of the base power supply circuit is connected to the discharge electrode side terminal of the capacitor. An output terminal of a pulse power supply circuit is connected to a primary winding of the pulse transformer. The base voltage and the pulse voltage can be controlled independently, and it becomes possible to apply a steep pulse with large output power to the discharge electrode.

Electric dust collector

Growing community of inventors

Tokyo, Japan

Osamu Kawabata