Mitsubishi Electric Corporation

Mitsubishi Denki Kabushiki Kaisha

Hiroyasu Iwabuki

Takaaki Takahara

Hiroto Mizutani

Ryota Kondo

Satoshi Murakami

Yoshihiro Takeshima

Kosuke Nakano

Hajime Toyoda

Akihiko Iwata

Kazufumi Tanaka

Kohei Onda

Hiroyuki Akita

Masatsugu Nakano

Yu Hirotani

Takuya Nakanishi

Masahiro Iezawa

Yasushi Nakayama

Akihiro Suzuki

Masato Matsubara

Hiroyuki Higashino

Yusuke Higaki

Tomokazu Sakashita

Koji Kise

Yuki Ishii

Takuya Sakai

Yasushige Mukunoki

Hitoshi Kidokoro

Kei Hayase

Tatsuya Kitamura

Ryo Shinohara

Takuya Yabumoto

Hiroshi Kurushima

Hideyuki Sotome

Hiroyuki Waku

Hideki Sugita

Keisuke Iwasawa

Takaya Muto

Yasunori Otsuka

A period from when switching elements S, Sat first diagonal positions in a full-bridge inverter are turned off at the same time to when switching elements S, Sat second diagonal positions are turned on at the same time, is defined as T, and a period from when the switching elements S, Sat the second diagonal positions are turned off at the same time to when the switching elements S, Sat the first diagonal positions are turned on at the same time, is defined as T. With a total length of Tand Tset to be constant, the lengths of Tand Tare controlled to be changed every switching cycle.

Power conversion device

An output terminal of a contact type charger connected to an AC power supplyand being for boosting or stepping down an input voltage, and an output terminal of a non-contact type charger for receiving power in a non-contact manner are connected to an input terminal of a DC/DC converter via an integrated bus, a DC link capacitor is connected between an AC/DC converter and an isolated DC/DC converter included in the contact type charger, an integrated capacitor is connected to the integrated bus, and a control circuit adjusts a DC voltage of the DC link capacitor or the integrated capacitor such that at least one of power losses or a total power loss of the contact type charger, the non-contact type charger, and the DC/DC converter is reduced.

Power conversion device having a configuration for simultaneous wired and wireless charging

A power conversion device includes: a main body including a substrate to which a power conversion unit and a coil are provided; and a first heat dissipation portion which holds the substrate and dissipates heat of the substrate, wherein the substrate is formed by one sheet, the coil is formed integrally with the substrate, the first heat dissipation portion is fixed to a substrate first surface of the substrate, a heat dissipation second surface of the first heat dissipation portion has a coil cooling portion opposed to and abutting on a part where the coil is formed, of the substrate.

Power converter

A magnetically coupled reactor and a DC/DC converter are provided between a DC power supply and an inverter. A first smoothing capacitor is provided between the DC power supply and the coupled reactor. A second smoothing capacitor is provided between the DC/DC converter and the inverter. A controller is provided in order to control switching operations of the inverter and the DC/DC converter. The controller causes semiconductor switching elements composing upper and lower arms of the DC/DC converter to perform complementary operations so as to be alternately turned on/off, and causes left and right legs to operate with their switching phases shifted from each other, thereby electric charges stored in both smoothing capacitors are discharged by energy loss in the coupled reactor and the DC/DC converter.

Power conversion device with controller to discharge smoothing capacitors

A DC capacitor and a leg are connected in parallel to a high-voltage-side power line and a low-voltage-side power line. The leg includes a plurality of semiconductor switching elements connected in series between the power lines with an output end, connected to a load, between the plurality of semiconductor switching elements. An attenuator for attenuating a resonance is connected to a main circuit loop formed of the DC capacitor, the high-voltage-side power line, the low-voltage-side power line, a semiconductor switching element in ON state, and a drain-source parasitic capacitance of a semiconductor switching element in OFF state.

A control circuit performs at least pulse width modulation control on a first leg and selects to perform pulse width modulation control and pulse frequency modulation control, to perform pulse width modulation control and phase shift modulation control, or to perform pulse width modulation control, pulse frequency modulation control, and phase shift modulation control on a second leg, based on comparison of a voltage conversion ratio between DC voltage of a DC capacitor and output voltage to a load with at least one threshold.

Power conversion apparatus

A power conversion device includes an input detector for detecting input parameters of the DC input to the inverter; an output detector for detecting output parameters of the DC output from the power converter device; a duty calculator for calculating a duty for the switching elements of the inverter; a frequency search range calculator for determining an upper limit and a lower limit of a frequency search range for determining the drive frequency after the operating condition is changed, using at least one parameter of the input parameters, the output parameters, and a duty parameter; and a frequency search processor for determining the drive frequency by searching the frequency search range.

Power conversion device with high power conversion efficiency

A power conversion device includes a first switching unit connected between a DC power supply and an inverter circuit, a resonant circuit connected to the input of the inverter circuit and formed by connecting a capacitor, a reactor, and a second switching unit, and a control unit, wherein, during a resonant operation period in which the first switching unit is controlled to be off and the second switching unit is controlled to be on, the control unit controls the inverter circuit to shift from a mode in which current flows back through one of upper and lower arms of the inverter circuit to a mode in which current flows back through the other arm, and provides a period in which the upper and lower arms for every phase of the inverter circuit are turned on simultaneously.

Power conversion device and electric motor drive device using same

A full-bridge inverter is configured with a parallel connection of a first leg and a second leg, and controlled in a dual-leg resonant mode in which a positive-side switching element of the first leg and a negative-side switching element of the second leg are turned on/off at the same time and a negative-side switching element of the first leg and a positive-side switching element of the second leg are turned on/off at the same time, and controlled in a single-leg resonant mode in which the positive-side switching element of the first leg and the negative-side switching element of the second leg, and the negative-side switching element of the first leg and the positive-side switching element of the second leg are turned on/off shiftedly in time by a phase shift amount.

Power conversion device with operation in dual-leg resonant mode or single-leg resonant mode

A diode rectifier rectifies an AC voltage output from a neutral-grounding three-phase AC power supply to a DC voltage. A smoothing capacitor smoothes the DC voltage rectified by the diode rectifier. An inverter converts the DC voltage smoothed by the smoothing capacitor into a desired AC voltage. A bidirectional switch and a Y capacitor are connected in series between one end of the smoothing capacitor and the ground. A detector detects a voltage across both ends of the smoothing capacitor. A controller drives the bidirectional switch in response to an output of the detector.

An electric motor drive device includes a smoothing capacitor and an inverter, and further includes an overvoltage protection unit for overvoltage protection for the smoothing capacitor, and a phase short-circuit control unit. The overvoltage protection unit includes: a discharge circuit having a discharge resistor and an IGBT connected in series; and a first determination circuit which determines, with determination delay, that smoothing capacitor voltage exceeds first set voltage, and turns on the IGBT. The phase short-circuit control unit is provided in a control device for drive-controlling the inverter and includes a second determination circuit which determines, with a determination period longer than the determination delay of the first determination circuit, that smoothing capacitor voltage exceeds second set voltage lower than the first set voltage, to perform phase short-circuit control for the inverter.

Electric motor drive device

During regenerative control of an inverter circuit, when a path between a DC power supply and a smoothing capacitor is in a disconnection state, a control circuit of a power conversion device performs control while switching between first control in which upper switching elements within the inverter circuit are turned on and all lower switching elements are turned off and second control in which the lower switching elements are turned on and all the upper switching elements are turned off, every predetermined switching period.

Power converter for controlling switching elements during regenerative control of an inverter

A rotating electric machine with a built-in control device that can be downsized. The rotating electric machine with a built-in control device includes a rotor including a permanent magnet of sensor use provided on a rear side of a rotor shaft, a front side housing fixed with a first bearing supporting a front side of the rotor shaft, a motor frame including a rotor and a stator, a heat sink fixed with a second bearing supporting the rear side of the rotor shaft, a control substrate mounting a rotary sensor, a microcomputer, and a driving circuit. The microcomputer controls the driving circuit based on signals from the rotary sensor and drives a plurality of switching elements. At least one of a smoothing condenser and a noise reduction coil, connected to the switching elements, is arranged at a far rear side of the control substrate.

Rotating electric machine with a built-in control device and electric power assist steering system

A motor drive control device for electric power steering includes: a switching element for supplying current to a motor; a smoothing capacitor for reducing ripple current due to the switching element; a control board on which a drive circuit for controlling the switching element and a control circuit capacitor are mounted; a control signal line for supplying a control signal from the control board to the switching element; an electric connection member electrically connecting the switching element and the smoothing capacitor; and a heatsink portion in which the switching element is arranged in an embedded manner, wherein the electric connection member is arranged between the switching element and the control board, and the control circuit capacitor and the smoothing capacitor are arranged in a space between the electric connection member and the control board.

Motor drive control device for electric power steering

A semiconductor switch circuit includes a plurality of switching units connected in series between a high-voltage node and a low-voltage node, and a plurality of diodes provided in association with the plurality of switching units, respectively. Respective cathodes of the plurality of diodes are connected to the plurality of switching units, respectively, and the anode of the diode associated with the switching unit connected to the low-voltage node receives a predetermined power supply voltage. Each switching unit includes a semiconductor switching device, a gate drive circuit driving the semiconductor switching device, and a DC-DC converter receiving a DC voltage from a cathode of the associated diode and supplying drive power to the gate drive circuit.

Growing community of inventors

Chiyoda-ku, Japan

Hiroyasu Iwabuki