Hitachi Industrial Equipment Systems Co., Ltd.

Hitachi, Ltd.

Hitachi Car Engineering Co., Ltd.

Daigo Kaneko

Takahiro Suzuki

Yoshitaka Iwaji

Tsunehiro Endo

Kazuaki Tobari

Kiyoshi Sakamoto

Tomofumi Okubo

Hajime Uematsu

Daisuke Maeda

Hiromi Inaba

Akira Yamazaki

Daisuke Kori

Kouki Yamamoto

Yusaku Onuma

Ikuo Yamato

Kento Mochizuki

Masakazu Hase

Yoshiyuki Taguchi

Seikichi Masuda

Takeshi Shinomiya

Naoto Ohnuma

Toshifumi Sakai

Yoichiro Arakawa

To prevent demagnetization of a permanent magnet synchronous rotating machine, a rotating machine control device according to the present invention is a rotating machine control device comprising: a power converter having a switch part on each of a positive side and a negative side for each phase; and short circuit detection unit for detecting a short circuit of the switch part, wherein a command to turn on positive-side switches and negative-side switches of a plurality of phases of the switch part is issued in the case where the short circuit detection unit detects the short circuit.

Rotator control device, rotator system, vehicle, electric car and electric generation system

Provided is a drive device for an alternating current motor which performs vector control on sensorless driving of the alternating current motor in an extremely low speed region without applying a harmonic voltage intentionally while maintaining an ideal PWM waveform. A current and a current change rate of the alternating current motor are detected, and a magnetic flux position inside of the alternating current motor is estimated and calculated in consideration of an output voltage of an inverter which causes this current change. The current change rate is generated on the basis of a pulse waveform of the inverter, and hence the magnetic flux position inside of the alternating current motor can be estimated and calculated without applying a harmonic wave intentionally.

Drive device for alternating current motor and electric motor vehicle

When applying a high frequency voltage which alternates on positive and negative sides to a permanent magnet synchronous motor, a driving system of synchronous motor switches the applied voltage phase by 120 degrees successively and applies resultant voltages to three phases. A pulsating current generated by applying a high frequency voltage is detected at timing of elapse of a predetermined time &#x394;t since an output voltage of at least one phase has changed from a state in which all output voltages of the three phases of a power converter are positive or negative. Current detection is conducted by using a DC resistor or a phase current sensor provided on a DC bus. A magnetic pole estimation unit calculates the rotor magnetic pole position of the permanent magnet synchronous motor on the basis of differences between positive side and negative side change quantities in three-phase currents obtained from detected current values.

Driving system of permanent magnet synchronous motor

Current command values are used instead of detected current values to estimate axis error by calculation. An axis error command value is generated according to a speed command value, and a difference between the generated axis error command value and the estimated axis error value is used to control an estimated frequency value.

Highly responsive permanent magnet motor controller

A motor controller capable of suppressing a large speed change generated at the time of changeover from a synchronous operation mode to a position feedback operation mode and implementing even acceleration characteristics regardless of the load torque by estimating a torque of a permanent magnet motor in the synchronous operation mode for driving the permanent magnet motor and setting an initial value of a current command value in a position sensor-less operation mode on the basis of information of the torque estimated value.

Motor controller, washing machine, air conditioner and electric oil pump

An apparatus for controlling the drive of an electric motor, having a current detector for detecting the current through an externally connected electric motor; a controller for generating a control signal to control the electric motor on the basis of the current detected by the current detector and the speed command for specifying the rotational speed of the electric motor; wherein the apparatus includes a load estimator for estimating the mechanical load condition associated with the electric motor on the basis of the current detected by the current detector and the speed command, and the controller controls the electric motor current on the basis of the detected current, the speed command and the estimated load condition.

Driving apparatus and driving system for electric motor

A synchronous motor driving apparatus having a power converter which applies AC variable voltages having variable frequency to a synchronous motor includes a pulsating current application unit for applying pulsating current to the synchronous motor and a magnetic pole position presumption unit. The magnetic pole position presumption unit detects two current values &#x394;Idcpand &#x394;Idcpon the positive side and two current values &#x394;Idcnand &#x394;Idcnon the negative side of the pulsating current and presumes the magnetic pole position of the synchronous motor on the basis of difference between change rates of &#x394;Idcp&#x2192;&#x394;Idcpand &#x394;Idcp&#x2192;&#x394;Idcp

Synchronous motor driving apparatus

In order to control the position of a mobile body without using a position detector, a magnetic pole position of a rotor of a synchronous motor is estimated based on electrical quantities in relation to electric power supplied to the synchronous motor and then the mobile body position is estimated based on the estimated magnetic pole position.

Apparatus, method or system for controlling mobile body

An AC motor control apparatus that is applicable to commonly used PM motors and capable of detecting the magnetic pole position with simple algorithm. The AC motor control apparatus comprises an inverter for applying arbitrary AC power to an AC motor and a controller for sending a control signal to the inverter. The controller comprises a ripple current generator for supplying a ripple current to the AC motor and a magnetic pole position estimator. The magnetic pole position estimator observes at least two current values of the ripple current for both positive and negative sides of the ripple current to estimate the magnetic pole position of the AC motor.

Growing community of inventors

Hitachi, Japan

Daigo Kaneko