Hokkaido University

Omron Corporation

Toshiba Mitsubishi-electric Industrial Systems Corporation

Utsunomiya University

Calsonic Kansei Corporation

Marelli Corporation

Dynax Corporation

Omrom Corporation

Casio Computer Co., Ltd.

Satoshi Ogasawara

Takashi Hyodo

Masatsugu Takemoto

Shunsuke Ohara

Yushin Yamamoto

Fumihiro Okazaki

Hiroyuki Tokusaki

Hirohito Funato

Wataru Kodaka

Koji Yamaguchi

Agnes Hadinata

Kenichi Takezaki

Kousuke Aoki

Wataru Hino

Koji Harada

Takemoto Masatsugu

A common mode filter circuit comprises a common mode transformer unit, an inverter, and a capacitor unit. Each of the first common mode transformer, the second common mode transformer, and the third common mode transformer comprises a first secondary wound wire, a second secondary wound wire, a third secondary wound wire, and a primary wound wire. A ratio of a number of turns of the primary wound wire to a number of turns of the first secondary wound wire, a ratio of a number of turns of the primary wound wire to a number of turns of the second secondary wound wire, and a ratio of a number of turns of the primary wound wire to a number of turns of the third secondary wound wire are each 3:1 in each of the first common mode transformer, the second common mode transformer, and the third common mode transformer.

Common mode filter circuit and drive device

A planar transformer includes: a primary side planar air core coil; a secondary side planar air core coil; a primary side planar core; and a secondary side planar core. The secondary side planar air core coil is arranged so as to be spaced from the primary side planar air core coil in the winding center axis direction of the primary side planar air core coil, the secondary side planar air core coil having a non-facing portion configured not to face the primary side planar air core coil in the winding center axis direction. The primary side planar core and the secondary side planar core are stacked on outer sides of the primary side planar air core coil and the secondary side planar air core coil in the directions of the winding center axes, respectively.

Planar transformer and DC-DC converter

A power supply control device according to one or more embodiments may be provided to: control a power conversion device that has a configuration in which a resonant circuit is provided on an output side of a matrix converter including switching circuits having snubber elements, and that performs AC-AC conversion of output from a multi-phase AC power supply. The power supply control device performs control such that: the output current, which has a phase difference caused by the resonant circuit, is negative during a period in which an absolute value of a positive-going output voltage that is output from the power conversion device increases while the output current is positive during a period in which the absolute value of a negative-going output voltage increases; and a polarity of the output current does not change within a period in which the snubber element is discharged.

Power supply control device, power conversion system, and power supply control method

A power conversion device, including: a voltage detector that detects a common mode voltage generated upon a switching operation of a power semiconductor device; a voltage superimposer that superimposes the common mode voltage detected by the voltage detector onto an output of the power conversion device to cancel the common mode voltage having a frequency greater than or equal to a switching frequency generated upon the switching operation of the power semiconductor device; and a residual voltage detector that detects the common mode voltage of the power conversion device superimposed by the voltage superimposer. The voltage superimposer includes a feedback mechanism for adding and superimposing the common mode voltage detected by the residual voltage detector onto the output of the power conversion device. The voltage detector includes a first choke coil and a first capacitor.

Power conversion device

A power supply control device according to one or more embodiments may be provided, in which a power conversion device has a configuration in which a resonant circuit is provided on an output side of a matrix converter using switching circuits including snubber elements so as to perform AC-AC conversion of output from a multi-phase AC power supply. The power conversion device is controlled to make an amplitude of an output current, a phase of the output current and an instantaneous reactive power as close to a control target as possible. The amplitude and the phase of the output current and the instantaneous reactive power are derived based on: an input voltage and a phase of a multi-phase current input to the power conversion device; and characteristics of the resonant circuit.

A power conversion device that converts electric power by having a power semiconductor element perform a switching operation includes a voltage detector detecting a common mode voltage generated in the switching operation of the power semiconductor element, a voltage control power supply that generates a voltage opposite in polarity to and as high as the common mode voltage with a circuit that amplifies power of the common mode voltage detected by the voltage detector, and a voltage superimposition structure canceling the common mode voltage not lower than a switching frequency generated in the switching operation of the power semiconductor element, by superimposing the voltage generated by the voltage control power supply on an output from the power conversion device.

Power conversion device canceling a common mode voltage

A direct current (DC)-DC converter includes: a transformer; a half bridge circuit provided on a primary side of the transformer; a synchronous rectification circuit provided on a secondary side of the transformer; and a controller configured to switch a power semiconductor device for rectification of the synchronous rectification circuit at a duty ratio and a phase corresponding to an input voltage of the half bridge circuit and an output current of the synchronous rectification circuit.

DC-DC converter

To reduce eddy current loss in a supporting member of a rotor of an axial gap motor, and improve efficiency, the motor includes a rotor, and stators arranged opposite to the rotor. The rotor has a disc-shaped supporting member, having a plurality of mounting holes in each of which a permanent magnet segment is installed. In the stators, a plurality of field windings is arranged for generating a rotating magnetic field. The axial gap motor is provided with notches extending radially between each of the mounting holes of the supporting member in which a permanent magnet segment is fitted, and an outer peripheral edge of the supporting member.

Axial gap motor

A power conversion circuit uses a multiphase AC power source as an input and has a plurality of bidirectional switches each of which is connected to each phase of the multiphase AC power source. A switching control circuit controls the states of the plurality of bidirectional switches and switches a combination of two phases of the multiphase AC power source, relating to interphase voltage to be outputted from the power conversion circuit to a load side. A resonant circuit is connected to an output side of the power conversion circuit. The switching control circuit, at a time of switching of the combination of the two phases that output the interphase voltage to the load side, switches the states of the bidirectional switches relating to the switching, by soft switching.

Power conversion device that converts AC to AC

The problem is to provide an axial gap motor using non-rare-earth magnets, as an axial gap motor capable of suppressing reduction in magnet torque and increasing reluctance torque. A solution to the problem is given by an axial gap motor, which has a rotor, and a pair of statorsarranged opposite to the rotorso that the rotoris sandwiched between the stators through a gap G in a direction of rotation axisof the rotor, in which the rotorhas a plurality of non-rare-earth magnetsarranged as separated from each other along a circumferential direction around the rotation axis, and a plurality of magnetic membersarranged through a non-magnetic memberor the like between the plurality of non-rare-earth magnets, in which the magnetic permeability of the plurality of magnetic membersis larger than that of the plurality of non-rare-earth magnets, and in which the plurality of non-rare-earth magnetsand the plurality of magnetic membersdefine opposite facesS of the rotorto the pair of stators

Growing community of inventors

Sapporo, Japan

Satoshi Ogasawara