Kabushiki Kaisha Toshiba

Saburou Souma

Chihiro Okado

Tatsuaki Ambo

Shinichi Toda

Ikuo Yasuoka

Yoshihito Nomura

A power converter for an electric locomotive includes an insulating transformer, an AC/DC converter, an inverter, a PWM controller, and a voltage controller. The insulating transformer is supplied with high-voltage AC power from an AC overhead wire to convert a high voltage to a low voltage and output low-voltage AC power. The AC/DC converter receives the low-voltage AC power and performs AC/DC conversion. The inverter receives an output from the AC/DC converter and performs DC/AC conversion for supply to a load. The PWM controller outputs a PWM control signal having a predetermined pattern, the pattern for removing specific harmonic components from an output of the inverter or attenuating the specific harmonic components to at most a predetermined level. The voltage controller controls a DC output voltage of the AC/DC converter to control an output voltage of the inverter.

Power converter for electric locomotive

A control equipment for a resistance welding machine for welding a material by the Joule's heat generated in the material by applying an electric power to the material, including an inverter for converting a DC voltage to an AC voltage by pulse width modulation control, a transformer having a primary winding to which the AC voltage is applied and having a secondary winding which supplies an AC current to the material, and a control unit for generating an AC current reference with a rectangular waveform of a specified frequency, comparing the AC current reference with an output current of the inverter to obtain an error, and for PWM controlling the inverter so that the error becomes zero.

Growing community of inventors

Tokorozawa Saitama, Japan

Saburou Souma