Mitsubishi Electric Corporation

Shinya Matsushita

Kazunori Hatakeyama

Shinsaku Kusube

Tsutomu Makino

Kenta Yuasa

Shota Kamiya

Takuya Shimomugi

Kazunori Sakanobe

Naoki Wakuta

Yosuke Shinomoto

Syota Kamiya

Masahiro Fukuda

Takashi Yamakawa

Yohei Kato

Katsuhiko Saito

Hirokuni Shiba

Yasushi Kuwabara

Takanori Omori

An outdoor unit includes: a heat exchanger to exchange heat between refrigerant and air; a first air blower and a second air blower to blow air on the heat exchanger; a compressor drive unit to drive a compressor compressing the refrigerant, the compressor drive unit including a power device; a cooling fin to cool the power device; a cooling-fin-temperature detection unit to detect temperature of the cooling fin; and a position determination unit to determine a position of the first air blower and a position of the second air blower by using the temperature of the cooling fin.

Outdoor unit, indoor unit, and air conditioner

A heat pump device includes a compressor including a motor, a heat exchanger, an inverter, and an inverter control unit. The inverter control unit generates a drive signal for the inverter. When the compressor is heated, the inverter control unit applies, to the motor, a high-frequency voltage with which the motor cannot be rotationally driven; estimates a magnetic pole position indicating a stop position of a rotor of the motor; determines an amplitude and a phase of a voltage command based on an estimation result of the magnetic pole position and a necessary amount of heat, and generates a drive signal.

Heat pump device, air conditioner, and freezer

A power conversion device includes a printed wiring board on which an alternating-current power-supply input part, a converter circuit part to convert alternating-current power to direct-current power, an inverter circuit part to convert direct-current power converted by the converter circuit part to alternating-current power, an alternating-current power-supply output part to output alternating-current power converted by the inverter circuit part, and a conductive pattern to electrically connect the alternating-current power-supply input part, the converter circuit part, the inverter circuit part, and the alternating-current power-supply output part to one another are provided, and a busbar that has a plate-like shape with a plane direction thereof perpendicular to a plane direction of the printed wiring board, is arranged to overlap the conductive pattern in plan view, and includes two or more connecting portions that are in contact with the conductive pattern.

Power conversion device

A heat pump device includes an inverter control unit for controlling an inverter. The inverter control unit includes a constraint-energization control unit that, during operation standby of a compressor, determines whether heating to the compressor is necessary, on the basis of a refrigeration stagnation amount in the compressor, and, when having determined that heating to the compressor is necessary, selects, according to the refrigeration stagnation amount, any one of direct-current energization for supplying a direct-current voltage to the motor and high-frequency energization for supplying a high-frequency voltage having a frequency higher than a frequency during a normal operation to the motor, so as to output a constraint energization command for carrying out constraint energization of the motor; and a driving-signal generating unit that generates a driving signal on the basis of the constraint energization command.

Heat pump device, and air conditioner, heat pump water heater, refrigerator and freezing machine including heat pump device

A heat pump device includes: a compressor including a compression mechanism compressing a refrigerant and a motor driving the compression mechanism; an inverter unit applying a voltage for driving the motor; an inverter control unit generating a driving signal for driving the inverter unit; and temperature sensors detecting temperatures of the compressor, wherein the inverter control unit includes a normal operation mode in which a refrigerant is compressed by performing a normal operation of the compressor and a heating operation mode in which a heating operation of the compressor is performed by applying, to the motor, a high-frequency voltage, and in the heating operation mode, the inverter control unit determines an amplitude and a phase of a voltage command for generating the high-frequency voltage on a basis of a temperatures detected by the temperature sensors and a necessary amount of heat specified in advance.

An object of the present invention is to maintain a heating amount constant when a compressor is heated at the time of shutdown of the compressor, regardless of the influences of production tolerance and environment variations. An inverter control unit causes an inverter to generate a high-frequency AC voltage having a de-energized section in which a voltage applied from the inverter to a motor is zero between a section in which the voltage is positive and a section in which the voltage is negative. At this time, the inverter control unit detects a value of a current flowing to the inverter in a detection section residing from immediately before a start of the de-energized section to immediately after an end of the de-energized section, and causes the inverter to generate a high-frequency AC voltage adjusted according to the detected current value.

Heat pump device, heat pump system, and method for controlling inverter

A heat pump device includes an inverter control unit outputting PWM signals to an inverter; a current detection unit detecting a current value flowing in the inverter and outputting the current value after reducing a current value having a first frequency or higher in detected current value; and a drive-signal stop unit that, when the current value output from the current detection unit is equal to or larger than an interruption level, stops output of PWM signals to the inverter. Particularly, the inverter control unit generates a voltage command value such that the voltage command value becomes a value equal to or larger than a lower limit determined according to the first frequency and generates PWM signals based on generated voltage command value and a carrier signal, thereby causing a voltage output time to the motor to be a predetermined time or longer.

A heat pump device capable of efficiently and reliably preventing a liquid refrigerant from stagnating in a compressor an air conditioner, a heat pump water heater, a refrigerator, and a freezing machine including the heat pump device. The configuration is such that, when the compressor is under operation standby, a high-frequency voltage synchronizing with a carrier signal is supplied to the compressor motor to carry out the locked energization of the compressor motor. From respective inter-phase voltages, respective phase voltages, or respective phase currents of the compressor motor for a plurality of high-frequency energization cycles, the detection values for one high-frequency energization cycle are restored. A power value calculated using the restored detection values for one high-frequency energization cycle is controlled to coincide with a heating power command necessary for discharging the liquid refrigerant stagnated in the compressor to the outside of the compressor.

Heat pump device, and air conditioner, heat pump water heater, refrigerator, and freezing machine including heat pump device

A heat pump device includes: a compressor that compresses a refrigerant; a motor that drives the compressor; a wiring switching unit that switches a wiring structure of the motor; an inverter that applies a desired voltage to the motor; and an inverter control unit that generates a PWM signal for driving the inverter, that includes, as an operation mode, a heating operation mode in which a heating operation is performed on the compressor and a normal operation mode in which a refrigerant is compressed by performing a normal operation on the compressor, and that controls a switching operation of the wiring switching unit in accordance with an operation mode.

Heat pump device, heat pump system, air conditioner, and freezer

A heat pump device includes a compressor including a compression mechanism that compresses a refrigerant and a motor that drives the compression mechanism, an inverter that applies a voltage for driving the motor, a converter that applies a voltage to the inverter, an inverter control unit that generates a driving signal for driving the inverter, and a converter control unit that generates a driving signal for driving the converter. The inverter control unit includes a heating-operation-mode control unit that controls a driving-signal generating unit such that the driving-signal generating unit outputs, as inverter driving signals, PWM signals for heating the compressor without rotationally driving the motor by feeding a high-frequency current that the motor cannot follow in a heating operation mode.

Heat pump device, air conditioner, and freezer that efficiently heats refrigerant on standby

An adder adds a phase &#x3b8;plus, which is n times a size of 60 degrees, to a phase output from a phase switching unit and outputs the phase as a voltage command phase &#x3b8;. A voltage generation unit generates voltage command value based on the voltage command phase output by the adder and outputs the command value. A drive-signal generation unit, based on an output from the voltage generation unit generates drive signals corresponding to respective switching elements of an inverter, and outputs respective generated drive signals to the corresponding switching elements of the inverter, and generates a high-frequency AC voltage in the inverter.

Heat pump device, heat pump system, and a control method of three-phase inverter

A voltage-command correction-value computation unit outputs a correction value for correcting a voltage command value according to a bus voltage. A multiplier calculates a voltage command value acquired by correcting the voltage command value based on the correction value. A voltage-command generation unit generates and outputs three-phase voltage command values based on the corrected voltage command value calculated by the multiplier and a phase. A PWM-signal generation unit generates six drive signals corresponding to switching elements of an inverter based on the three-phase voltage command values outputted by the voltage-command generation unit and a carrier signal. The PWM-signal generation unit outputs the generated drive signals to the corresponding switching elements of the three-phase inverter, to cause the inerter to generate a high-frequency AC voltage.

Heat pump device, heat pump system, and method for controlling three-phase inverter

A selection unit switches between a phase &#x3b8;p and a phase &#x3b8;n different from the phase &#x3b8;p substantially by 180 degrees, and outputs one of them in synchronization with a carrier signal. A voltage-command generation unit generates and outputs three-phase voltage command values Vu*, Vv* and Vw* based on the phase outputted by the selection unit. A PWM-signal generation unit generates three-phase voltage command values Vu*', Vv*&#x2032; and Vw*&#x2032; by correcting the three-phase voltage command values Vu*, Vv* and Vw* outputted by the voltage-command generation unit according to a predetermined method, and generates six drive signals corresponding to switching elements of the inverter based on the three-phase voltage command values Vu*&#x2032;, Vv*&#x2032; and Vw*&#x2032; and the carrier signal. The PWM-signal generation unit outputs the generated drive signals to the corresponding switching elements of the three-phase inverter, to cause the inverter to generate a high-frequency AC voltage.

An air conditioner equipped with a compressor, an indoor heat exchanger and an outdoor heat exchanger includes: an inverter circuit that drives a motor of the compressor; an inverter-power detecting unit that detects power of the inverter circuit; a PWM-signal generating unit that inverter-current detecting unit generates PWM signals for controlling the inverter circuit; a voltage-command-value generating unit that outputs voltage command values to the PWM-signal generating unit; and an accumulation detecting unit that detects accumulation of a liquid refrigerant within the compressor and outputs a detection result to the voltage-command-value generating unit, wherein when accumulation of a liquid refrigerant within the compressor is detected, the voltage-command-value generating unit outputs the voltage command value so that power of the inverter circuit has a predetermined power value.

Air conditioner controlling prheating power of compressor and mechanism providing preheating power for compressor

A heat pump device that can efficiently feed a high-frequency current to an electric motor and effectively heat a compressor includes a compressor including a compression mechanism configured to compress a refrigerant and a motor configured to drive the compression mechanism, heat exchangers, an inverter configured to apply a voltage to the motor, and an inverter control unit configured to drive the inverter. The inverter control unit includes a stagnation detecting unit configured to determine whether heating of the compressor is necessary and notify the determination result and a high-frequency-alternating-current-voltage generating unit and a PWM-signal generating unit configured to shift to a heating operation mode when the heating is necessary and, in the heating operation mode, generate PWM signals to provide, based on a heating time carrier signal having two or more frequencies, a period in which a reflux current flows.

Growing community of inventors

Tokyo, Japan

Shinya Matsushita