Hitachi, Ltd.

Hitachi Industrial Products, Ltd.

Naoki Kunihiro

Takeshi Nakayama

Katsumi Ishikawa

Kiyoshi Nakata

Masanori Matsumoto

Shinji Sugimoto

Masaaki Endo

Yasushi Hayasaka

Motonobu Iizuka

Daisuke Kori

Tetsuo Fujigaki

Makoto Ito

Kazutoshi Ogawa

Takeo Takagi

Tomomi Kanazawa

Shuichi Terakado

Atsushi Fukunaga

Shoichi Maruyama

Yoshihiro Yasui

Takeshi Shinomiya

Yasunori Otsuki

Kuniaki Otsuka

Kazuo Nishihama

Toshifumi Sakai

Masakatsu Sato

Hiroyuki Shirata

Masatoshi Koike

Yuki Fukuoka

This three-phase AC motor drive device is provided with: a load; an inverter devicefor driving the load; an MCOK_A_connected between the inverter deviceand the load and electrically connecting or disconnecting the inverter deviceto or from the load; a voltage detectorhaving terminals respectively connected to the circuits of at least two phases to detect the voltages between the three phases; and a current detectorfor detecting the currents of the three phases. In the connection from the inverter deviceto the load, the inverter device, the MCOK_A_, the voltage detector, the current detector, and the load are aligned in this order.

Three-phase AC motor drive device, rail vehicle equipped with same, and three-phase AC motor drive method

A rotating electric machine comprises a field winding provided on a rotor iron core and a neutral ring supported independently of the field winding, wherein: the field winding and the neutral ring are electrically connected to each other through a connecting wire; the neutral ring is disposed spaced with respect to the rotor iron core; and the connecting wire absorbs the stress difference between the field winding and the neutral ring when a centrifugal stress is applied.

Rotating electric machine or wind power generation system

Growing community of inventors

Tokyo, Japan

Naoki Kunihiro