Hitachi Automotive Systems, Ltd.

Hitachi Astemo Ltd.

Hitachi Automotive Systems Steering, Ltd.

Yoshitaka Sugiyama

Kazuya Yamano

Masaki Kashima

Takafumi Hara

Shigehisa Aoyagi

Hiroyuki Ota

Masaki Kodato

Toshiyuki Ajima

Yasuhito Nakakuki

Atsushi Yoshitake

Masaki Itabashi

Tsukasa Miyajima

Tadashi Suganuma

Masahiko Ushimura

Kazuya Watanabe

A microcomputer stores an offset correction value for correcting an offset of a detected current along with a pulse shift for each of a detected current of a maximum phase to which power is supplied for the longest time among three phases and a detected current of a minimum phase to which power is supplied for the shortest time among the three phases, and corrects the detected current of each of the phases with use of the stored offset correction values for the detected current of the maximum phase and the detected current of the minimum phase.

Motor control apparatus

An applied voltage decision unitperforms in parallel, a process of determining three-phase AC commands V* to V* of a voltage applied to a motor by an inverter based on a position, of a rotor of a motor, detected by a position sensor with an output A, and a process of determining three-phase AC commands V* to V* of the voltage applied to the motor by the inverter based on a neutral point voltage VN of the motor. A PWM modulatoralternately outputs a PWM signal according to the three-phase AC commands V* to V* and a PWM signal according to the three-phase AC commands V* to V* to the inverter. A control device determines whether or not the position sensor with the output A has failed by comparing the position, of the rotor, detected by the position sensor with the output A with a position, of the rotor, estimated from a neutral point voltage VN of the motor.

Control device

Provides are a control device for a three-phase synchronous motor in which a position detection accuracy of a rotor can be improved when one three-phase synchronous motor is driven by a plurality of inverters, and an electric power steering device using the same. A control device for a three-phase synchronous motor includes: a three-phase synchronous motor including a first three-phase winding and a second three-phase winding; a first inverter connected to the first three-phase winding; a second inverter connected to the second three-phase winding; a first control device that controls the first inverter on the basis of a rotor position of the three-phase synchronous motor; and a second control device that controls the second inverter on the basis of the rotor position of the three-phase synchronous motor. The first control device estimates the rotor position on a basis of a neutral point potential of the first three-phase winding and a neutral point potential of the second three-phase winding.

Control device for three-phase synchronous motor and electric power steering device using the same

Provided is a control apparatus for a power steering apparatus, and a power steering apparatus using it that can reduce electromagnetic noise with the aid of a spread spectrum, thereby realizing stabilized motor control. The control apparatus for the power steering apparatus includes a PWM carrier period setting portion configured to set a natural number of PWM carrier periods within one period of a control period and also changeably set a length of the PWM carrier period, a motor current detection execution portion configured to detect a motor current during the control period, a motor rotational angle detection execution portion configured to detect a motor rotational angle during the control period, and an execution timing setting portion configured to set a timing at which the motor current is detected by the motor current detection execution portion or a timing at which the motor rotational angle is detected by the motor rotational angle detection execution portion, based on the control period set by the control period setting portion.

Control apparatus for power steering apparatus and power steering apparatus using the same

Provided are a power steering device and a control device for a power steering device, which are capable of reducing power consumption. The power steering device includes a current detection number setting circuit configured to set the number of times of detection of a DC bus current value by a current detecting circuit to a first predetermined number over a first predetermined cycle of a PWM period when the steering-state signal indicative of a steering operation state is received, and to set the number of times of detection so that the number of times of detection becomes smaller than the first predetermined number over the first predetermined cycle of the PWM period when a steering-state signal indicative of a non-steered state is received.

Power steering device and control device for power steering device

A transverse gradient current Ic which is larger than a basic assist current Ib is outputted, as a current command value, to motor driving section when direction correspondence judgment sectionjudges that rotation directions of first and second rotation angle signals &#x3b8;and &#x3b8;correspond with each other, when an advancing phase judgment sectionjudges that a phase of the second rotation angle signal is advanced, and when a phase variation judgment sectionjudges that a phase advance state of the second rotation angle signal &#x3b8;continues.

Electric power steering device and electric power steering device control device

Electric power steering system has steering mechanism; input and output shaft side rotation angle sensors detecting rotation angles of input and output shafts; operation circuit calculating command current for an electric motor; rotation direction judging circuit judging whether rotation directions of the input and output shafts are identical; advanced-phase judging circuit judging which phase of input and output shaft side rotation angle signals (S, S) is advanced; normal/reverse input judging circuit judging that (i) when both rotation directions are identical and Sis advanced, input is normal input and (ii) when both rotation directions are identical and Sis advanced, input is reverse input; and command current correcting circuit. The command current correcting circuit corrects the command current so that when the normal input is judged, torque in the same direction as input shaft rotation direction generated by the electric motor is greater than a case of reverse input judgment.

Growing community of inventors

Machida, Japan

Yoshitaka Sugiyama