Fuji Electric Co., Ltd.

Central Japan Railway Company

Tomotaka Nishijima

Koji Maruyama

Michio Tamate

Toshiaki Murai

Tadashi Sawada

Yoshiyasu Hagiwara

Masayuki Tobikawa

Ayako Saga

Hirokazu Kato

Yasushi Matsumoto

Kei Sakanoue

Hiroki Shimoyama

Ayako Ichinose

Junichi Ishii

Toshie Kikuchi

Toshiya Kaneko

A controlling apparatus includes a storage unit for storing, for each sampling period, a combination of a primary frequency of connected induction motors and the amplitude of a voltage command value, and a gradient detection unit for calculating a value corresponding to an increase in the amplitude of the voltage command value divided by an increase in the primary frequency, and for outputting a failure signal upon determining, when a result of the division is less than a predetermined reference value, that the plurality of induction motors include at least one induction motor having a phase sequence that includes incorrect wiring with respect to the power converter.

Power system, power converter controlling apparatus, and electric vehicle having the power system

In a power supply device, the bridge circuit is configured by connecting, in parallel, a plurality of series circuits of an inverse-parallel connection circuit of a semiconductor switch and a diode. A control unit controls switching of a semiconductor switch so that a voltage v between AC terminals becomes zero voltage in equal periods &#x3b1; before and after a center point shifted from one zero crossing point in one cycle of the input current by a compensation period (angle) &#x3b2; calculated from a voltage applied to a resonance circuit constituted by the power receiving coil and a resonance capacitor Cand an induced voltage of the power receiving coil, and becomes a positive-negative voltage whose peak value is the voltage Vbetween DC terminals in other periods.

Power supply device

In a power supply device the bridge circuit is configured such that a plurality of series circuits of two inverse parallel connection circuits of a semiconductor switch and a diode are connected in parallel. The power supply device includes a control unit configured to control the semiconductor switch such that a voltage between AC terminals of the bridge circuit becomes a zero voltage only during a prescribed time period before and after two zero crossing points in one cycle of the input current and such that the voltage becomes a positive-negative voltage in which the output voltage is a peak current value during other time periods. Consequently, a power factor of the power receiving circuit is improved and a loss of an entire device is inhibited, and a size and a cost of the entire device may be reduced.

In a power supply device, the bridge circuit including a plurality of switching arms which is an inverse-parallel circuit of a semiconductor switch and a diode. The power supply device includes a control unit. The control unit switches the semiconductor switch such that a voltage v between AC terminals becomes a positive-negative voltage whose peak value is the voltage Vbetween the DC terminals only during prescribed time periods before and after a point that has deviated from each zero crossing point ZCP of a current i by a prescribed compensation period &#x3c6; and such that the voltage v between the AC terminals becomes a zero voltage during the other time periods, and sets the compensation period &#x3c6; such that a time period during which the voltage v between the AC terminals becomes a zero voltage is the shortest.

Power supply device with a resonant bridge circuit control unit

Growing community of inventors

Hyogo, Japan

Tomotaka Nishijima