Kabushiki Kaisha Toshiba

Naoki Oomura

Kazunobu Nagai

Toshimitsu Aizawa

Atsuyuki Hiruma

Sadao Ikeda

Shinichi Kominato

Shingo Ikawa

Sari Maekawa

Minoru Awazu

Yukihisa Hasegawa

Atsushi Nagasawa

Junichiro Hagura

Jun Sodesawa

Hiroyuki Ishida

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 motor driving apparatus according to an embodiment includes a brushless motor. The motor driving apparatus includes a position sensor that outputs a position detection signal in synchronization with a phase of an induced voltage of a coil of the brushless motor. The motor driving apparatus includes a semiconductor integrated circuit that controls driving of the brushless motor by supplying a pseudo sine-wave driving voltage from an energization terminal to the coil of the brushless motor based on the position detection signal and a command signal that prescribes driving of the brushless motor.

Semiconductor integrated circuit and motor driving apparatus

A motor control unit or a semiconductor integrated circuit device for an air conditioner is provided. The motor control unit includes a current detector that detects a coil wound current of the permanent magnet motor; a coordinate transformer that transforms the coil wound current detected by the current detector into a d-axis current indicating a magnet flux component and a q-axis current indicating a torque component perpendicular to the magnet flux component; a position estimator that estimates a rotational position of the rotor based on an induced voltage of the permanent magnet motor; a current controller that calculates a command d-axis voltage based on a command d-axis current and the d-axis current detected by the current detector, and that calculates a command q-axis voltage based on a command q-axis current and the q-axis current detected by the current detector; an electrifier controller that electrifies the coil wound based on the command d-axis voltage and the command q-axis voltage; and a start-up controller that detects an oscillation of the rotor during a start-up operation and, if a velocity direction of the oscillation corresponds with a rotational direction of a forcible commutation, the start-up controller starts the forcible commutation so as to start an acceleration of the rotor by following an acceleration pattern.

Motor control unit and air conditioner having the same

A positioning unit including a rotational position detector detecting a rotational position of a motor; a control phase angle generator generating a control phase angle corresponding to the detected rotational position; a rotational speed detector detecting a rotational speed; a position controller calculating a target rotational speed based on a difference between a target stop position and the rotational position and specifying a command d-axis voltage at zero when the difference is greater than a predetermined reference value, and at a predetermined exciting voltage when the difference is equal to or less than the reference value; a speed controller generating a command q-axis voltage based on the difference between the target rotational speed and the rotational speed; a coordinate transformer performing rotational coordinate transformation of the command d-axis voltage and the command q-axis voltage to form a three-phase command voltage; and a conductive signal generator generating three-phase conductive signal.

Motor positioning unit

A motor control unit including a rotational position detector detecting a rotational position of a brushless DC motor; a current detector detecting a current of the brushless DC motor; a coordinate transformer executing rotational coordinate transformation of the current by a control phase angle and obtaining a d-axis current and a q-axis current; a current controller generating a command d-axis voltage based on a d-axis current error, and generating a command q-axis voltage based on a q-axis current error; a coordinate transformer generating a three-phase command voltage by the control phase angle; a conductive signal generator; and a position controller that, when executing a positioning operation, maintains the command d-axis current at a constant value and the command q-axis current at zero, and that controls the control phase angle based on a difference between a target stop rotational position and a rotational position detected by the rotational position detector.

Motor control unit

A method and apparatus for controlling a brushless DC motor which has a permanent magnet rotor and a 3-phase stator winding for applying a rotating magnetic field to the permanent magnet rotor. A specified reference voltage is compared with the stator winding terminal voltages for each phase. The rotor position is detected from the output of these comparison circuits based on the induced voltages generated in the stator windings which are not conducting when the motor is rotated. The stator windings which conduct current are controlled in response. Furthermore, a specific conduction pattern is supplied to each stator winding when the rotor is stopped, and a reference output determined for the conduction pattern is compared with the output of the comparison circuits when the stator windings are conducting. Abnormalities are detected based on the comparison results of the comparison circuit.

Method and apparatus for controlling a brushless DC motor that indicates

Method and apparatus for controlling a brushless DC motor

A method and apparatus of controlling an air conditioner. The discharge temperature of a compressor and the indoor heat exchanger temperature are steadily controlled to set temperatures as close as possible, suppressing hunting of the frequency of an inverter. A temperature sensor is provided for detecting the temperature of the indoor heat exchanger or the discharge temperature of the compressor. A control unit is further provided, and judges as to in which temperature zone among at least preset four temperature zones the detected temperature is. Then, the control unit outputs frequency control signals to the inverter to perform the following operations: when the detected temperature is in the lowest temperature zone, the output frequency of the inverter is increased at a predetermined speed; in a lower intermediate temperature zone the frequency is slowly increased; in an upper intermediate temperature zone below a set temperature the current frequency is maintained; and in a temperature zone above the set temperature the frequency is decreased at a predetermined speed.

Growing community of inventors

Minato-ku, Japan

Naoki Oomura