Omron Corporation

Nagaoka University of Technology

Katsutaka Tanabe

Yasuhiro Tsubota

Masao Mabuchi

Takao Mizokami

Kotaro Nakamura

Nobuyuki Toyoura

Kazuyoshi Imamura

Teruyuki Maeda

Mio Yamada

Junichi Itoh

Kenichi Inoue

Akihiro Funamoto

Junichiro Yamada

Kazumi Tsuchimichi

Katsumi Ohashi

Koji Ando

Seiji Oka

Takuji Kumagai

Atsuo Minato

Yuji Tsurukawa

Arata Yoneda

A power conversion apparatus includes an inverter for drive controlling a plurality of switching elements, drive circuits, a control circuit, a current detection part, an overcurrent detection circuit, and a protection circuit. The protection circuit, which receives a detection signal that the overcurrent detection circuit outputs to indicate detection of overcurrent, outputs a signal to the drive circuits for turning off a switching element that has been turned on by a control signal from the control circuit for a predetermined time.

Power conversion apparatus and control method of inverter

A switching element with a small current capacity is provided to be able to be used in a DC-DC converter. The DC-DC converter includes a switching circuit in which a first switching element, a second switching element, a third switching element, and a fourth switching element are connected in series, a flying capacitor that is connected between a connection portion between the first switching element and the second switching element and a connection portion between the third switching element and the fourth switching element, a reactor that is connected between a connection portion between the second switching element and the third switching element and a positive electrode of an input unit, and a control circuit that turns on/off the switching element, in which the control circuit turns on/off the switching elements so that a peak value in a reactor current becomes equal to or smaller than a predetermined value.

DC-DC converter

A voltage transform part transforms the direct-current power input to an input part. A first input and output part outputs the transformed direct-current power to a battery unit and to which direct-current power is input from the battery unit. A conversion part converts the direct-current power input to the input part into alternating-current power. A second input and output part outputs the alternating-current power to a power system or a load and to which an alternating-current power is input from the power system. The conversion part converts the alternating-current power input to the second input and output part into direct-current power. The second voltage transform part transforms the direct-current power converted by the conversion part and transforms the direct-current power input to the first input and output part. The conversion part converts the direct-current power transformed by the second voltage transform part into alternating-current power.

Power storage system, voltage transformer and power storage power conditioner

A power conditioner that suppresses distortion in a waveform of a sinusoidal generated voltage includes a first and second group including two switches each connected in inverse parallel and in series. The power conditioner alternately turns on and off both switches in the first group at a prescribed chopping frequency and alternately turns on and off both switches in the second group at a PWM frequency higher than the chopping frequency. If control is performed with a dead-time provided in the on/off timing for both switches in each group, the power conditioner adjusts and controls the on/off duty for the second group switches to correspond to the effective on drive in one switch by each diode during the dead-time for each switch in the first group.

Power conditioner

A power conditioner that suppresses generation of voltage spikes in a part of a generated sinusoidal voltage waveform. An offset between the timing of chopping, which depends on whether the voltage difference between the voltage of a third pulse voltage series and a sinusoidal voltage is positive or negative, and the timing of the switching between on/off duty cycles of a seventh and eighth switch is calculated, and the on/off duty cycles of the seventh and eighth switches are controlled on the basis of the timing offset.

An electric power conversion device comprises switching elements making up a push-pull converter, a pulse transformer T, a rectification diode D , a rectification diode D , a choke coil L, a smoothing capacitor C, a DC magnetic deviation prevention means , and an inverter . The DC magnetic deviation prevention means detects the coil currents I , I flowing in the primary windings M , M of the pulse transformer T. By controlling (shortening) the on time of the switching element having a greater amount of current, the coil currents I , I are balanced (I &equals;I ), thereby preventing the magnetic deviation phenomena of the pulse transformer T.

Electric power conversion device with push-pull circuitry

Growing community of inventors

Moriyama, Japan

Katsutaka Tanabe