Kabushiki Kaisha Toshiba

Yutaro Kitamori

Takashi Fujita

Teruyuki Ishizuki

Takahisa Kageyama

Sho Sato

Ryuta Hasegawa

According to one embodiment, an over-voltage prevention device includes a first short-circuit device provided between a secondary side of a wound-rotor induction machine and a frequency converter configured to excite the secondary side by a three-phase AC current and having a function of short-circuiting between phases of the three-phase AC current, resistors each connected between the first short-circuit device and the frequency converter for each phase, and second short-circuit devices connected respectively to the resistors in parallel and having a function of short-circuiting between the frequency converter and the secondary side of the wound-rotor induction machine.

Over-voltage prevention device and current rectifying circuit

According to one embodiment, an over-voltage prevention device is provided between a secondary-winding side of a wound-rotor induction machine and a frequency converter configured to excite the secondary-winding side of the wound-rotor induction machine through a three-phase excitation power supply line. The over-voltage prevention device includes a first short-circuit device having a function of short-circuiting between phases of the excitation power supply line, and a second short-circuit device having a function of short-circuiting between phases of the excitation power supply line with a short-circuit impedance greater than a short-circuit impedance of the first short-circuit device.

Growing community of inventors

Fuchu, Japan

Yutaro Kitamori