Mitsubishi Electric Corporation

Keisuke Uemura

Koichi Arisawa

Kazunori Hatakeyama

Takuya Shimomugi

Yosuke Shinomoto

Kenji Iwazaki

Takashi Yamakawa

Satoru Ichiki

Akihiro Tsumura

Shinsaku Kusube

Kenta Yuasa

Yuichi Shimizu

Shigeo Umehara

Yuji Takayama

Makoto Tanikawa

Noriyuki Matsubara

Shinichiro Ura

Shinya Toyodome

Atsushi Tsuchiya

Takaaki Takahara

Yasuhiko Wada

Keisuke Mori

Kenji Takahashi

Kazuchika Tsuchida

Takahiko Kobayashi

Haruka Matsuo

Motoya Suzuki

Koyo Matsuzaki

Takashi Matsumoto

Norikazu Ito

Mitsuo Kashima

Tomohiro Kutsuki

Masaru Shinozaki

Shota Kamiya

Yoshikazu Yaji

Shunsuke Kubota

Ryuji Momose

Takamitsu Yamada

Yunqing Fan

Yuya Kondo

Tomoaki Gyoda

This disclosure provides an outdoor unit for an air-conditioning apparatus with improved reliability. The outdoor unit () includes a housing whose inside is divided into a fan chamber () and a machine chamber (). A compressor and a reactor that are heat-generating components are provided in a lower area of the machine chamber (). An electric board () including a printed circuit board () and an electric component (), and an electric component box () constituted by an inner box () and an outer box () and accommodating the electric board are provided above the heat-generating components. A lower face of the inner box (first thermal insulation plate) and a lower face of the outer box (second thermal insulation plate) constitute a double thermal insulation plate ().

Outdoor unit for air-conditioning apparatus

A power conversion device includes a rectification unit that rectifies first alternating current (AC) power supplied from a commercial power supply, a capacitor connected to an output end of the rectification unit, an inverter that converts power output from the rectification unit and from the capacitor into second AC power, and outputs the second AC power to a load including a motor, which inverter is connected to both ends of the capacitor, and a control unit that controls operation of the inverter to output the second AC power from the inverter to the load to reduce current flowing to the capacitor, which second AC power includes a pulsation that depends on a pulsation of power flowing from the rectification unit to the capacitor. No discharge circuit and no overvoltage protection circuit are provided for the capacitor.

Power conversion device, motor drive unit, and refrigeration cycle apparatus

A power converter includes a converter, a smoothing capacitor, an inverter, and a single calculator. The converter includes a switching element and rectifies a power supply voltage applied from an alternating-current power supply. The smoothing capacitor smooths a rectified voltage output from the converter into a direct-current voltage including a ripple. The inverter converts the direct-current voltage smoothed by the smoothing capacitor into an alternating-current voltage for a motor. The calculator performs control such that a first physical quantity representing an operation state of the converter is equal to a second physical quantity representing an operation state of the inverter.

Power converter, motor driver, and refrigeration cycle applied equipment

A power converting apparatus includes: a reactor including a first end and a second end, the first end being connected to an alternating-current power supply; a rectifier circuit connected to the second end of the reactor and including at least one switching element, the rectifier circuit converting an alternating-current voltage output from the alternating-current power supply into a direct-current voltage; and a detecting unit that detects a physical quantity indicating an operation state of the rectifier circuit, wherein the number of times of switching of the switching element is changed depending on the operation of the rectifier circuit.

Power converting apparatus, and motor driving apparatus

A heat pump apparatus includes: a compression mechanism that compresses a refrigerant; a motor that drives the compression mechanism; an inverter that applies a voltage to the motor; and an inverter control unit that generates a drive signal for driving the inverter, based on a carrier signal, in which the inverter control unit periodically changes a carrier frequency of the carrier signal in a heating operation mode in which the refrigerant is heated, and generates the drive signal such that a period of time during which a voltage represented as a real vector is applied to the motor is kept constant regardless of the changed carrier frequency.

Heat pump apparatus, air conditioner, and refrigerator

A power conversion apparatus includes a converter circuit converting AC voltage output from an AC power supply into DC voltage. The converter circuit includes unit converters. The power conversion apparatus includes a low current-oriented controller the unit converters to cause current corresponding to a single phase to flow through a current detector, and a high current-oriented controller controlling operation of the unit converters based on a result of comparison between a duty command and a carrier signal, where the duty command is generated based on detection values detected by the current detector and a voltage detector. When the detection value detected by the current detector is less than or equal to a first threshold, the low current-oriented controller is activated, and when the detection value detected by the current detector is greater than the first threshold, the high current-oriented controller is activated.

Power conversion apparatus, motor drive apparatus, blower, compressor, and air conditioner

An outdoor unit includes a housing, a heat exchanger, an electric component box, a substrate, and a heat dissipator including multiple fins. The fins each have a first end situated in a windward side of an air passage formed between adjacent ones of the fins, and the first end faces the electric component box. When the heat dissipator and the electric component box are viewed from above, a first clearance gap having a first width and a second clearance gap having a second width greater than the first width are formed between the first end and the electric component box. The second clearance gap is situated closer to a back panel than the first clearance gap.

Outdoor unit and air conditioner

A motor drive device includes a reactor, a converter circuit, a capacitor, an inverter circuit, and overcurrent determination units. The converter circuit converts a first AC voltage output from an AC power supply into a DC voltage. The capacitor smooths a second voltage on the DC side of the converter circuit. The inverter circuit converts DC power stored in the capacitor into AC power. One of the overcurrent determination units determines overcurrent based on a detected value of the first AC current, flowing between the AC power supply and the converter circuit. Another overcurrent determination unit determines overcurrent based on a detected value of the second DC current, flowing between the converter circuit and the capacitor. The converter and inverter circuits stop operating when the determination result of one of the overcurrent determination units indicates an overcurrent.

Motor drive device, blower, compressor, and air conditioner

A motor drive apparatus includes a reactor, a converter connected to an alternating current power supply via the reactor, a smoothing capacitor connected between output terminals of the converter, and an inverter that converts a direct current voltage output from the smoothing capacitor into an alternating current voltage to be applied to a motor and outputs the alternating current voltage. The motor drive apparatus includes a plurality of operation modes for controlling conduction of switching elements of the converter and causing the converter to operate in different modes of operation, and changes operation of at least one of the switching elements of the converter and the inverter according to the operation mode when a bus voltage indicates an excessive value.

Motor drive apparatus, blower, compressor, and air conditioner

An air conditioner includes a compressor to compress a refrigerant used in a refrigeration cycle, a converter to generate a DC voltage, an inverter to generate three-phase AC voltages from the DC voltage, a motor to produce a driving force for driving the compressor with a plurality of coils, the three-phase AC voltages being applied to the coils, a connection switching unit to switch connection states of the coils between a first connection state and a second connection state, and a controller to detect an abnormality of the connection switching unit.

Air conditioner and driving device

A converter device includes: a power conversion circuit including a reactor and a switching element, rectifying a voltage of alternating-current power supplied from an alternating-current power supply to a direct-current voltage, and boosting and outputting the direct-current voltage; a current detector detecting a current flowing in the reactor; a filter circuit filtering a first signal detected by the current detector; and a control unit generating a control signal on the basis of a carrier and a second signal generated by the filter circuit and controlling, on the basis of the control signal and with a first period, the switching element, the first period being a period of the carrier. The filter circuit cuts off a repetition frequency component in the first period and passes a repetition frequency component in a second period, the second period being longer than the first period.

Converter device, motor drive device and air conditioner

A direct-current power supply apparatus includes: a reactor having one end connected to an alternating-current power supply; a bridge circuit, connected to an opposite end of the reactor, converting an alternating-current first voltage output from the alternating-current power supply into a direct-current voltage; and a current detector detecting an alternating current flowing between the alternating-current power supply and the bridge circuit. The reactor reduces an inductance in accordance with an increase of the alternating current and, when the alternating current exceeds a first current, has an inductance lower than one third of an inductance at which a current does not flow in the reactor. The bridge circuit performs an active operation when the detection value of the alternating current is larger than or equal to the first current and performs a passive operation when the detection value of the alternating current is lower than the first current.

Direct-current power supply apparatus, motor drive control apparatus, blower, compressor, and air conditioner

A power converting apparatus includes: a bridge circuit that includes at least two legs each including switching elements connected in series, and converts an alternating-current voltage output from an alternating-current power supply into a direct-current voltage; a power-supply current detecting unit that detects a current from the alternating-current power supply; a zero crossing detecting unit that detects a voltage polarity of the alternating-current power supply; and a control unit that controls ON and OFF of the switching elements depending on outputs of the power-supply current detecting unit and the zero crossing detecting unit, in which a dead time that is set for switching and includes a change in the voltage polarity of the alternating-current power supply is longer than a dead time that is set for switching and does not include a change in the polarity.

Power converting apparatus, motor driving apparatus, and air conditioner

A power converting apparatus includes: a reactor that includes a first terminal and a second terminal, the first terminal being connected to an alternating-current power supply; a bridge circuit that is connected to the second terminal of the reactor, includes at least one or more switching elements, and converts an alternating-current voltage output from the alternating-current power supply into a direct-current voltage; a power-supply current detecting unit that detects a current from the alternating-current power supply; and a control unit that controls ON and OFF of the switching elements depending on a current value detected by the power-supply current detecting unit, in which two or more current thresholds for controlling ON and OFF of the switching elements are included.

An outdoor unit includes a housing that includes a front panel and a back panel facing the front panel. The outdoor unit further includes a bell mouth provided on the front panel and a heat dissipator that dissipates heat generated by electric components. A windward end surface and a leeward end surface of the heat dissipator are, when viewed from above, placed in a region between a virtual surface and the back panel, the virtual surface being a virtual surface that is in contact with an end of the bell mouth on a side of the back panel and is parallel to an inner surface of the front panel.

Growing community of inventors

Tokyo, Japan

Keisuke Uemura