Kabushiki Kaisha Toshiba

Nsk Corporation

Toshiba Home Appliances Corporation

Toshiba Consumer Electronics Holdings Corporation

Sari Maekawa

Kazunobu Nagai

Nobuyuki Suzuki

Shin Kumagai

Shigeru Fukinuki

Toshimitsu Aizawa

Tsuyoshi Hosoito

Kohei Hasegawa

Isamu Nitta

Takeshi Shibayama

Minoru Awazu

Atsuhiko Kuzumaki

Yukihisa Hasegawa

Naoki Oomura

Takenori Yasuzumi

Sadao Ikeda

Shinichi Kominato

Toshikazu Sekihara

Junichiro Hagura

Shuting Li

A motor control integrated circuit according to embodiments outputs predetermined PWM signals to an inverter circuit that drives a synchronous motor and is configured to perform on-off control on a plurality of three-phase bridge connected switching elements in accordance with the PWM signals to convert direct current into three-phase alternating current, and includes: a PWM generation unit configured to generate the signals based on a received speed command value and output the PWM signals; and a current detection unit configured to detect differential values of phase currents at a predetermined time point that is fixed within a period of a carrier wave used for PWM control, based on the carrier wave and a signal generated by a current detector for detecting current conducted to the synchronous motor, wherein the PWM generation unit calculates a speed of the synchronous motor based on the differential values and then, based on the speed, generates the PWM signals to be applied to the synchronous motor.

Motor control integrated circuit

A power conversion device includes: a first power conversion circuit that converts power inputted from outside and outputs the converted power to a second power conversion circuit connected to the first power conversion circuit via a DC link, which outputs the converted power to a load; smoothing capacitors provided in an output part of the first power conversion circuit and an input part of the second power conversion circuit; a first and second common mode current extraction circuits provided in an input part of the first power conversion and second power conversion circuits; and a virtual neutral potential line that connects the first and second common mode current extraction circuits; a DC link filter circuit that includes a Y-shaped capacitor connected between the DC link part and the virtual neutral potential line.

Power conversion device and power conversion system

An inverter device includes a switch circuit configured by series-connecting two N-channel semiconductor switching elements in opposite directions so that the switch circuit makes or breaks electrical connection between a DC power supply and an inverter circuit, and a control circuit carrying out a protecting operation in which when the control circuit outputs a control signal to control switching of the inverter circuit and an operating condition is met, the control circuit stops output of the control signal to turn off all switching elements configuring the inverter circuit and the switch circuit. In the protecting operation, the switch circuit is turned off after output of the control signal has been stopped so that changes in drain-source voltages and drain currents of the N-channel semiconductor switching elements are rendered slower.

Inverter device and power steering device

A motor control device driving a motor via an inverter circuit includes a current sensing element, a PWM signal generation unit and a current detection unit. The PWM signal generation unit is configured to generate three-phase PWM signals in a manner such that the current detection unit is capable of detecting two-phase currents at two fixed time-points within a carrier period of the PWM signal. A duty of one of the three-phase PWM signals is increased/decreased to both phase lag side and phase lead side with reference to any phase. A duty of another phase PWM signal is increased/decreased to both phase lag side and phase lead side with reference to any phase away one half of the carrier period from the reference phase. A duty of the other phase PWM signal is increased/decreased to either phase lag side or phase lead side with reference to any phase.

Motor control device, air conditioner, washing machine and refrigerator

A switch driving circuit electrically opens and closes a switch circuit including two N-channel type semiconductor switching elements series connected in a reverse direction, thereby electrically opening and closing a path between a DC power supply and an inverter circuit. The switch driving circuit has a reference potential point in common with the inverter circuit and supplies an opening/closing control signal to the switch circuit. The switch driving circuit includes a half bridge circuit including two semiconductor switching elements series connected between a driving power supply and the reference potential point. Two protection diodes are connected in parallel to the semiconductor switching elements respectively. At least one current blocking diode is configured to block current from flowing from the reference potential point through the diode to the switch circuit side when the DC power supply is connected to the inverter circuit in reverse polarity.

Switch driving circuit, inverter apparatus and power steering apparatus

A motor control device includes a PWM signal generation unit configured to increase/decrease a duty in both directions of phase lag side and phase lead side regarding a first phase of three-phase PWM signal pattern. The PWM signal generation unit is configured to increase/decrease a duty in one of the directions of phase lag side and phase lead side regarding a second phase. The PWM signal generation unit is configured to increase/decrease a duty in a direction opposite to that of the second phase with reference to any phase of the carrier-wave period regarding a third phase. A timing point adjusting unit is configured to detect two-phase currents at timing points fixed in the carrier-wave period and to adjust a detection timing point so that the current is detectable at a variable timing point regarding at least one phase when the two-phase currents become undetectable at the fixed timing points.

Motor control device and air conditioner

A motor control device includes a PWM signal generating unit comparing PWM command voltage and carrier wave with each other to generate pulse signal so that duty is increased or decreased in both directions of phase lag and phase lead with one phase within carrier period as reference regarding one phase of three-phase PWM signal. The unit generates pulse signal so that duty is increased or decreased in one of the directions with one phase as reference regarding another phase. The unit generates pulse signal so that duty is increased or decreased in direction reverse to the one direction with one phase as reference regarding the other phase. The unit generates three-phase PWM signal pattern so that a current detecting unit is capable of detecting two-phase current in synchronization with advent of two predetermined time-points within carrier wave period of PWM signal with first to third phases being normally fixed.

Motor control device

A motor control device includes a PWM signal generation unit configured to increase/decrease duty in both leading and lagging directions regarding a phase in which the duty becomes maximum among three-phase PWM signals. The unit is also configured to increase/decrease the duty in one of leading and lagging directions regarding a phase in which the duty becomes minimum. Regarding a phase in which duty is intermediate between the phases, the unit is configured to increase/decrease duty in the other of the leading and lagging directions based on the phase, thereby generating a three-phase PWM signal pattern so that a current detection unit is capable of detecting two-phase currents at two time-points fixed within a carrier period of the PWM signal respectively. A duty compensation unit is configured to increase/decrease before and after changing an increasing/decreasing direction of three-phase duties, increasing/decreasing the duties to compensate for the duties.

A motor control device includes a torque computing section which computes an output torque of an electric motor which is capable of generating magnetic torque by permanent magnets and reluctance torque, a flux weakening angle computing section which determines an angle of a flux weakening current vector that is added to a reference current vector so that a command torque value and the computed torque value correspond with each other, a voltage acquiring section which acquires a terminal voltage of the motor, a flux weakening amplitude computing section which determines an amplitude of the flux weakening current vector so that the terminal voltage of the motor is not more than a maximum voltage applicable to the motor, and a command current computing section which computes a command current vector by adding the flux weakening current vector to the reference current vector.

A motor control device includes an inverter circuit having switching elements on/off controlled according to a predetermined PWM signal pattern to convert an input direct current to three-phase alternating current supplied to drive an electric motor. A phase current of the motor is detected based on a detection of the input direct current and the PWM signal pattern. A PWM signal generation unit which generates a three-phase PWM signal pattern to enable detecting two-phase currents twice in synchronization with four time-points within a carrier wave period of the PWM signal respectively and so that a detection of current follows a magnetic pole position of the motor. A current differential unit supplies, as current differential values, differences between twice detected current values regarding the two phases respectively, and a magnetic pole position estimation unit estimates the magnetic pole position of the motor based on the current differential values.

A motor controller is disclosed. The motor controller includes a current detector that is provided in a direct current side of a power converter and that detects direct current information. A determiner determines a size of an offset voltage contained in the detected current information. The determiner calculates the offset voltage by canceling a positive current component by a negative current component both pertaining to the same one phase and contained in the detected direct current information. A modifier modifies the detected direct current information based on the calculated offset voltage.

Motor controller

A motor control device includes an inverter circuit including a plurality of switching elements connected into a three-phase bridge configuration and converting a direct current into a three-phase alternate current, a current detecting element connected to a direct current side of the inverter circuit, thereby generating a signal corresponding to a current value, a PWM signal generating unit which determines a rotor position based on phase currents of the motor and generates a three-phase PWM signal pattern so that the signal pattern follows the rotor position, and a current detecting unit detecting phase currents based on the signal generated by the current detecting element and the PWM signal pattern. The PWM signal generating unit generates the three-phase PWM signal pattern so that the current detecting unit is capable of detecting two phase currents in synchronization with advent of two fixed time-points within a carrier period of the PWM signal respectively.

A motor control device includes a current detecting unit detecting current flowing into a motor winding, a speed/electrical angle estimating unit estimating a rotational speed and an electrical angle of the motor, based on the current, a load torque estimating unit estimating load torque to be developed by a load, from a torque current obtained based on the current and the electrical angle, a motor constant and inertia moment of the motor inclusive of the load, a load torque phase calculating unit calculating a phase of periodic fluctuation indicated by the load torque, a torque-compensating current determining unit determining a sinusoidal torque-compensating current, based on the load torque phase, and an amplitude/phase adjusting unit detecting speed fluctuation of the motor to adjust amplitude and phase of the torque compensating current by increasing or decreasing the amplitude and the phase so that the speed fluctuation is reduced.

Motor control device and electrical equipment with motor controlled thereby

A motor control device controlling an inverter to control an electric motor, includes a plurality of function sections, a voltage command generating section generating a d-axis voltage command and a q-axis voltage command, a voltage operational processing section, an input current operation section, a speed information generating section estimating a rotational speed of the motor based on at least one of a motor constant, a positional information generating section delivering positional information about a rotor, and a processor executing control software set by a user or a manufacturer. At least a part of the function sections are configured by hardware. The function section configured by the hardware is given at least one parameter retaining section. The parameter retaining section is configured so as to be readable/writable on the processor. The function section is configured by the hardware so as to be operated in a predetermined sequence.

Motor control device and electrical equipment provided with the same

A washer dryer including a DC power supply generator that generates a DC power supply from an AC power supply; a heat pump that circulates refrigerant between a compressor, a condenser and an evaporator; an air circulatory path that circulates air between the condenser and the evaporator; a first inverter circuit that receives the DC power supply to drive a compressor motor; a rotary tub disposed rotatably within an exterior tub; a rotary tub motor that directly drives the rotary tub at least during dehydration; a second inverter circuit that receives the DC power supply having an output terminal connected to windings of the rotary tub motor; a voltage detector that detects DC voltage occurring between the second inverter circuit and a power supply bus; a brake controller that controls the DC voltage within a predetermined range by controlling a regenerative electric power when braking is applied.

Growing community of inventors

Yokohama, Japan

Sari Maekawa