Mitsubishi Electric Corporation

Mitsuo Kashima

Yosuke Shinomoto

Tomohiro Kutsuki

Kenji Takahashi

Takuya Shimomugi

Shigeo Umehara

Shinya Toyodome

Kazunori Hatakeyama

Makoto Tanikawa

Tomomi Higashikawa

Koichi Arisawa

Keiichiro Shizu

Michio Yamada

Akiyoshi Muramatsu

Masato Handa

Takashi Matsumoto

Norikazu Ito

Keisuke Uemura

Keita Hatanaka

Masaki Kono

Yoshihiko Kinpara

Kiyoshi Eguchi

Katsuhiko Saito

Hideki Takahara

Hitoshi Tanifuji

Kouichi Arisawa

Shigeya Okada

Yuriko Takeda

A motor drive apparatus includes: a dq-axis current controller converting phase current flowing through a synchronous motor into d-axis current and q-axis current, and controlling the phase current by determining a voltage command based on the d-axis current and a d-axis current command as well as the q-axis current and a q-axis current command; a voltage amplitude calculating unit obtaining voltage amplitude; a speed controller controlling rotational speed of the motor by determining the q-axis current command based on a speed command, the rotational speed, and a speed droop amount that reduces the speed command; a flux weakening controller performing flux control to limit amplitude of voltage output to the motor by determining the d-axis current command based on the voltage amplitude and a first voltage limit value; and a speed droop controller controlling the speed droop amount based on the voltage amplitude and a second voltage limit value.

Motor drive apparatus

An estimation device includes a phase current determination unit, a time difference calculation unit, and an estimation unit. The phase current determination unit performs a determination process for determining values of phase currents based on the value of the bus current detected by a bus current detection unit and states of gate pulse signals. The time difference calculation unit calculates a difference between a detection time of the bus current used in a previous determination process and a detection time of the bus current used in a present determination process. The estimation unit estimates at least one of a position and a speed of an AC motor based on the values of the phase currents determined by the phase current determination unit and the difference calculated by the time difference calculation unit.

Estimation device and AC motor drive device

A motor drive device: a power conversion unit; a current detection unit that detects a phase current of the alternating-current motor; a position/speed specifying unit that specifies a magnetic pole position and a rotational speed of the alternating-current motor; a d-axis current pulsation generating unit that generates a d-axis current pulsation command based on q-axis current pulsation or a q-axis current pulsation command, which being in synchronization with the q-axis current pulsation or the q-axis current pulsation command and preventing or reducing an increase or decrease in amplitude of the voltage command; and a dq-axis current control unit that generates the voltage command for controlling the phase current on the dq rotating coordinates, which rotate in synchronization with the magnetic pole position, by using the magnetic pole position, the rotational speed, the phase current, the q-axis current pulsation or the q-axis current pulsation command, and the d-axis current pulsation command.

Motor drive device, compressor drive system, and refrigeration cycle system

A speed estimating device for an AC motor includes: a model deviation computing unit computing a model deviation based on a voltage, a current, and an estimated angular velocity of the AC motor; a first angular velocity estimating unit computing a first estimated angular velocity based on the model deviation; a second angular velocity estimating unit computing a second estimated angular velocity differing from the first estimated angular velocity in frequency, based on the model deviation; a compensation phase computing unit computing a compensation phase based on a disturbance frequency; and an estimated angular velocity calculator computing an estimated angular velocity of the AC motor based on the first estimated angular velocity and the second estimated angular velocity. Either one of the first estimated angular velocity and the second estimated angular velocity is computed based on the compensation phase.

Speed estimating device for AC motor, driving device for AC motor, refrigerant compressor, and refrigeration cycle apparatus

It provides an inverter main circuit converting a DC-voltage into three-phase AC-voltages, a DC-current detection unit detecting the DC-current value of a DC-current flowing in the main circuit, and an inverter control unit generating a drive signal for controlling operation of the main circuit using a voltage command value corresponding to each phase of the three-phase AC-voltages and a triangular-wave carrier. Using a time period during which the triangular-wave carrier monotonically increases or decreases as a unit period, the control unit provides control to alternately use, as the DC-current value for use in computation of the voltage command value, the DC-current value detected in the unit period in which the triangular-wave carrier monotonically increases and the DC-current value detected in the unit period in which the triangular-wave carrier monotonically decreases, for every voltage command value control period set to three times or more and an integer multiple of the unit period.

Inverter control device

A speed estimation apparatus for an AC motor includes a model deviation calculation unit, first and second angular velocity estimation units, and an adder. The deviation calculation unit calculates a model deviation based on a voltage, a current, and an estimated angular velocity of the motor. The first angular velocity estimation unit calculates a first estimated angular velocity as a low-frequency component including a DC component of a real angular velocity based on the model deviation. The second angular velocity estimation unit calculates a second estimated angular velocity as a high-frequency component of a real angular velocity based on a specific high-frequency component of the model deviation. The adder adds the first and second estimated angular velocities together. An addition value of the first and second estimated angular velocities is fed back as the estimated angular velocity to the deviation calculation unit.

Speed estimation apparatus for AC motor, driving apparatus for AC motor, refrigerant compressor, and refrigeration cycle apparatus

An electric motor drive unit includes a winding switching unit that switches a configuration of windings of an electric motor, a winding switching instruction unit that generates an instruction signal for the winding switching unit, and a winding configuration retention unit to which the instruction signal generated by the winding switching instruction unit is input, and if the input instruction signal has a first value, outputs a signal corresponding to the input instruction signal to the winding switching unit, and if the input instruction signal has a second value different from the first value, continues outputting a signal that has been output to the winding switching unit before the reception of the second value, the first value indicating an instruction on the configuration of the windings.

Motor drive unit, compressor, and air conditioner

An electric quantity of a power supply of a connection switching device for switching the connection state of a motor, or at least one electric quantity which varies with the first-mentioned electric quantity is detected, the result of the detection is used to detect or predict a fall of a voltage of the switching power supply. Based on the result of the detection or prediction, an inverter is so controlled as to stop the motor before the voltage of the switching power supply falls below the minimum voltage required for the operation of the connection switching device. Breakdown of the connection switching device can be prevented.

Motor driving apparatus and refrigeration cycle equipment

A synchronous motor control device includes: a DC power supply; an inverter main circuit; a three-phase synchronous motor; and an inverter control unit that outputs a PWM signal used to control the inverter main circuit. The inverter control unit includes: a PWM signal generation unit; a start-up control unit that outputs a start-up voltage command value to the PWM signal generation unit at the time of start-up; a steady state control unit that calculates a steady state voltage command value in a steady state and outputs the value to the PWM signal generation unit; and a steady state control parameter initial value calculation unit that outputs an initial value of a control parameter to the steady state control unit such that an output voltage vector from the inverter main circuit to the three-phase synchronous motor is consistent before and after switching from the start-up to the steady state.

Synchronous motor control device and method of controlling synchronous motor

The present invention includes a plurality of fan motors, first and second inverters for individually driving the fan motors, respectively, and one and a common control unit that performs a control arithmetic for each of the fan motors and generates an individual driving signal given to each of the inverters.

Indoor equipment and air conditioner

A synchronous motor control device includes a voltage detector, a current detector, an inverter main circuit, and an inverter control unit. The inverter control unit includes: a phase current reproduction unit that reproduces a direct current into phase currents flowing to a permanent magnet synchronous motor; a current coordinate transformation unit that transforms the reproduced phase current into current on a control coordinate axis of a rotating coordinate system; a current control unit that calculates a voltage command value of the permanent magnet synchronous motor in such a manner that the current on the control coordinate axis equals a specific value; and a limiter unit that limits the value of the voltage command value.

Synchronous motor control device, compressor drive system, and air conditioner

An inverter control device includes an inverter main circuit, a current detector, a voltage detector that detects a DC voltage between DC bus lines, and an inverter control unit that generates PWM signals to perform on/off control of a plurality of semiconductor switching elements respectively with a DC current and a DC voltage. The unit sets a carrier period of PWM signals to be 1/N times a calculation period in which the PWM signals are generated, performs detection of a DC current detected by the current detector in a 1/2 calculation period immediately before a calculation start timing for generating PWM signals, calculates an output voltage vector based on the detected DC current, and reflects PWM signals generated from the output voltage vector in one calculation period from a 1/2 calculation period after the calculation start timing to 3/2 control calculation periods after the same.

Inverter control device and air conditioner

A power conversion device is configured to have reactors and is configured to have chopper circuit units, connected in series, that chop the output of a rectifier configured to rectify an AC voltage from an AC power supply. The power conversion device includes: an AC switch disposed on a side closer to the AC power supply than the chopper circuit units; an AC reactor that is connected in parallel to the AC switch; and a switching control unit that stops the switching of the switching elements when the contact of the AC switch is open.

Power conversion device, motor drive control device equipped with power conversion device, compressor and blower equipped with motor drive control device, and air conditioner equipped with compressor or blower

A power conversion device includes a switching control unit that controls respective switching elements constituting a plurality of chopper circuits, a rectified-voltage detection unit, a bus-bar voltage detection unit, and a bus-bar current detection unit. The switching control unit includes an on-duty calculation unit that calculates a reference on-duty of respective drive pulses with respect to the switching elements based on a bus-bar voltage and a bus-bar current, an on-duty correction unit that corrects the reference on-duty to output on-duties of the respective drive pulses based on the bus-bar current, so that change amounts of respective reactor currents become substantially the same, and a drive-pulse generation unit that generates the respective drive pulses, based on the respective on-duties.

Power conversion device, motor drive control apparatus including the power conversion device, air blower and compressor including the motor drive control apparatus, and air conditioner including the air blower or the compressor

A power converter includes step-up means for varying a voltage applied by a power supply to a predetermined voltage, commutating means for performing a commutation operation for allowing a current flowing through the step-up means to flow through a second path, smoothing means for smoothing a voltage related to outputs of the step-up means and the commutating means to produce power and supplying the power to a load side, and control means for performing control related to voltage varying, such as stepping up, by the step-up means and controlling the commutation operation of the commutating means on the basis of at least one of a voltage and a current related to the step-up means.

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Tokyo, Japan

Mitsuo Kashima