Mitsubishi Electric Corporation

Mitsubishi Denki Kabushiki Kaisha

Tokyo Institute of Technology

Mitsubishi Denki K.k.

Japan Aerospace Exploration Agency

Akihiko Iwata

Takahiro Urakabe

Akihiro Suzuki

Takashi Hashimoto

Shigeki Harada

Masaki Yamada

Kenji Fujiwara

Tatsuya Okuda

Taichiro Tamida

Takashi Kumagai

Yoshihiro Ueda

Hiroshi Ito

Shigeo Ueguri

Tatsuki Okamoto

Masaru Kobayashi

Hirotoshi Maekawa

Yoichiro Tabata

Osamu Mori

Tetsuya Kojima

Kenichi Koyama

Masakazu Taki

Takayoshi Nagai

Takashi Ohsawa

Hiroshi Kobayashi

Takeshi Morimoto

Jun Someya

Takushi Jimichi

Tomohiro Sasagawa

Junichi Nishimae

Shinsaku Kusube

Ikuro Suga

Kenta Yuasa

Akihiro Tsumura

Kenichi Kawabata

Norikazu Ito

Toshiyuki Fujii

Satoshi Azuma

Kuniko Kojima

Takahiro Inoue

Tatsushi Sato

Shinji Murata

Hideaki Hayashi

Hajime Nakatani

Shigeo Takata

Toshiyuki Kikunaga

Yoshikazu Tsunoda

Hisatoshi Fukumoto

Matahiko Ikeda

Kikuo Izumi

Kazuhiko Hara

Kenji Yoshizawa

Shuta Ishikawa

Makoto Seto

Hiroyuki Sasao

Takeshi Oi

Masato Matsubara

Hiroyasu Iwabuki

Kiyoharu Anzai

Yoshikazu Ukai

Hitoshi Wakata

Kenyu Haruta

Shingo Tsuda

Yukimori Kishida

Tomoki Takegami

Mitsugu Takahashi

Noriyuki Matsubara

Atsushi Taneda

Yoshihiro Hatakeyama

Hirofumi Akagi

Teruaki Fukuoka

Akira Nishizawa

Hideaki Fujita

Akira Ikeda

Shuichi Nagato

Kazutoshi Kaneyuki

Masaaki Tanaka

Yuya Tanaka

Hiroshi Itoh

Takahiko Kobayashi

Masanori Mizuno

Taichiro Tsuchiya

Noboru Wada

Seiji Satou

Yasuo Onodera

Haruhiko Nagai

Masato Koyama

Tetsuaki Nagano

Hiroshi Nakatake

Shuhei Koyama

Yoshitomo Hayashi

Miwako Tanaka

Hitoshi Kidokoro

Akira Imanaka

Yoshihiro Taniguchi

Shinichi Ogusa

Yoshiteru Suzuki

Yoshibumi Minowa

Miyuki Takeshita

Junichiro Ishikawa

A motor control device includes: a power source device including a DC-output power conversion device having a first mode for outputting first voltage and a second mode for outputting second voltage higher than the first voltage; a power supply device; and a control device, and controls a motor. When a flying object takes off, the control device controls the power conversion device in the second mode. When the control device judges that flight information which is one or both of information of a motor parameter obtained along with control for the motor and information of an environmental factor relevant to the flight altitude satisfies a predetermined condition, or when the control device has received an operation mode signal for which the first mode is selected on the basis of the flight information during control for the motor, the control device controls the power conversion device in the first mode.

Motor control device

For connected-in-parallel N DC-DC converters (to N, where N is 3 or more), a first converter group on which PWM switching is performed with a first carrier, and a second converter group on which PWM switching is performed with a second carrier having a phase different from that of the first carrier, are provided. One or more of the DC-DC converters (to N) are assigned to each converter group. A plurality of drive modes in which the number of the DC-DC converters that are driven and the converter groups are set, are provided. The drive modes are switched through comparison between a preset threshold value and a total output of the N DC-DC converters (to N), and a ratio between total outputs in the first and second converter groups is set to fall within a predetermined range.

Power conversion device with parallel DC-DC coverters and multiple driving modes

A motor control device includes: a step-down device including a DC-output power conversion device having a first mode for outputting first voltage and a second mode for outputting second voltage lower than the first voltage; a power supply device; and a control device, and controls a motor. When a flying object takes off, the control device controls the power conversion device in the first mode. When the control device judges that flight information which is one or both of information of a motor parameter obtained along with control for the motor and information of an environmental factor relevant to the flight altitude of satisfies a predetermined condition, or when the control device has received an mode signal for which the second mode is selected on the basis of the flight information during control for the motor, the control device controls the power conversion device in the second mode.

A three-phase multilevel inverter is connected to a first direct-current voltage source having a first voltage. Single-phase inverters are each connected in series to a corresponding phase of the three-phase multilevel inverter, and include a second direct-current voltage source, respectively, each having a second voltage. Combined output voltages, which are combinations of boost voltages generated by the three single-phase inverters and output voltages of the three-phase multilevel inverter, are supplied to a load. The control device adjusts a common mode voltage of the combined output voltages to be within a predetermined allowable range, and variation ranges of the line voltages in the combined output voltages to satisfy a specified condition established with the second voltage as a reference.

Power conversion device with control circuit to adjust a common mode voltage of combined output voltages

A power converter includes an inverter circuit connected between the positive and negative terminals of a DC power supply, three single-phase bridge circuits each connected in series between an AC terminal of one of different phases of the inverter circuit and a motor, and a power conversion controller that generates gate signals to control operations of the inverter circuit and the three single-phase bridge circuits based on phase voltage commands. When a semiconductor switching element of the single-phase bridge circuits fails, the power conversion controller sets the output voltage of the single-phase bridge circuit of a phase to which the faulty semiconductor switching element belongs to zero to continue operation.

Power converter

A subtracting unit calculates a voltage deviation of an output voltage of a DC-to-DC converter from a target voltage. A feedback control variable calculator calculates a feedback control variable in each control cycle. In a control cycle in which a crossing of the output voltage and the target voltage is detected by a feedforward control determination unit, a feedforward control variable calculator calculates a feedforward control variable so that a change in the output voltage is prevented. A switching control signal generator generates a control signal for the DC-to-DC converter for controlling the output voltage, according to a summation of the feedforward control variable and the feedback control variable.

Power converter control device with feedforward

The power conversion device includes a multilevel boosting circuit and a smoothing capacitor for smoothing output voltage of the multilevel boosting circuit. The multilevel boosting circuit includes: a leg portion in which four semiconductor elements, i.e., a first diode, a second diode, a first switching element, and a second switching element are connected in series; and an intermediate capacitor connected between a connection point of the first diode and the second diode, and a connection point of the first switching element and the second switching element. When voltage of the smoothing capacitor becomes a reference voltage value or more, the control unit executes a protection mode to fix the first switching element and the second switching element in OFF states.

Power conversion device including a boosting converter for boosting output voltage from a DC power supply

The power conversion device includes: a boosting unit for boosting DC voltage, the boosting unit including a second switching element, a third switching element, a second reverse-current blocking element, and a third reverse-current blocking element which are connected in series, the boosting unit including an intermediate capacitor connected between a connection point between the second reverse-current blocking element and the third reverse-current blocking element, and a connection point between the third switching element and the second switching element; a smoothing capacitor which is connected in parallel to the boosting unit and smooths the DC voltage boosted by the boosting unit; and a control unit for turning on the third switching element so that the intermediate capacitor is charged to charge completion voltage of the intermediate capacitor.

Power conversion device with an intermediate capacitor and a smoothing capacitor

A laser diode driving power source of a laser machining device that radiates laser light emitted from an LD to a workpiece to machine the workpiece includes a power converter including a switching device, to supply a current to the LD, and a control unit to control a switching operation of the switching device. A value smaller than a value that is n times a time constant for laser machining is set as a switching period of the switching device in the control unit, the n is larger than 1, and the time constant for laser machining is a value obtained by dividing a surface roughness required for machining of the workpiece by a moving velocity of the workpiece.

Laser diode driving power source and laser machining device

Provided is an electrostatic capacitance detection device including: an electrode pair including a pair of electrodes, the electrode pair being arranged inside a compressor configured to compress refrigerant; a capacitor being connected in series to the electrode pair; an inverter having one of power lines connected to one end of series-connected electrode pair and capacitor, and is configured to drive the compressor, the power lines being used for driving the compressor; and a voltage detecting unit configured to measure a voltage between the pair of electrodes of the electrode pair.

Electrostatic capacitance detection device and power conversion apparatus

A converter supplies an output voltage, generated by stepping down or up an input voltage from a DC power supply, to an inverter for driving an AC motor. In the converter in a boost mode, a buck circuit is stopped, a boost circuit is operated, and a first bypass switch is turned on to form a path from the DC power supply to the boost circuit. In a buck mode, the boost circuit () is stopped, the buck circuit is operated, and a second bypass switch is turned on to form a path from the buck circuit to the inverter.

Power conversion device

A series connection body wherein a first backflow prevention elements, a second backflow prevention element, a first switching element and a second switching element are connected in series in this order; a reactor; a first output capacitor connected between a first end of the series connection body and a second end of the series connection body; and a second output capacitor connected between a connection point between the first switching element and the second switching element and a connection point between the first backflow prevention element and the second backflow prevention element are provided, a DC is inputted between an end of the reactor and the second end section of the series connection body, and power is supplied to a first load connected to both ends of the first output capacitor and a second load connected to both ends of the second output capacitor.

Power converter with different output voltages for plurality of loads

A laser diode-driving power supply includes a constant current source that supplies current to LDs, a switching element connected in parallel to the LDs, and a control unit that controls the constant current source and performs on-off control of the switching element. The control unit compares a first current command value and a second current command value for controlling current output from the constant current source, and when the second current command value input after the first current command value is smaller than the first current command value, applies to the LDs a voltage in the range of a voltage at which current flows through the LDs to a voltage less than the lasing threshold of the LDs when there is no output from the LDs.

Laser diode-driving power supply and laser machining apparatus

A refrigeration cycle apparatus includes: a refrigerant circuit, a use side heat exchanger, a pressure reducing device, and a heat source side heat exchanger; A fan is provided together with at least one, selected from between, the use side heat exchanger and the heat source side heat exchanger and that has a fan motor; a relay unit connected to a direct-current supply device via the direct-current circuit breaker; a resistor unit connected in parallel to the relay unit; a DC/AC converter configured to convert a direct-current voltage supplied from the direct-current supply device via either the relay unit or the resistor unit into an alternating-current voltage and to supply the alternating-current voltage to at least one, selected from between, the compressor motor and the fan motor; and an opening and closing control unit configured to bring the relay unit into an open state when the direct-current circuit breaker becomes open.

Refrigeration cycle apparatus

A power conversion device is provided that includes a rectifier, a booster circuit configured to boost an output voltage of the rectifier, a smoothing capacitor configured to smooth an output voltage of the booster circuit, and an inverter circuit configured to convert a DC voltage of the smoothing capacitor to an AC voltage and drive a motor forming a part of a device supplied with the voltage after the conversion. In addition, a reactor, a first backflow prevention element, a second backflow prevention element, a first switching element, a second switching element, an intermediate capacitor, and a controller configured to control the first switching element and the second switching element, are included.

Boost converter with flying capacitor and refrigeration circuit

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Tokyo, Japan

Akihiko Iwata