Hitachi Automotive Systems, Ltd.

Hitachi Astemo Ltd.

Hitachi Automotive Systems Steering, Ltd.

Masaki Kashima

Shigehisa Aoyagi

Yoshitaka Sugiyama

Toshiyuki Ajima

Takafumi Hara

Kazuya Yamano

Tatsuro Suzuki

Daisuke Goto

Kimihisa Furukawa

Tohma Yamaguchi

Hiroyuki Ota

Yawara Kato

Atsushi Hirata

Masaki Itabashi

Tadashi Suganuma

Eiichiro Ito

Atsushi Yoshitaka

Tatsuro Mitsuhira

Masahiro Seo

A steering device includes: an offset correction value storing section to store an offset correction value including a first offset correction value and a second offset correction value, the first offset value being a current value for correcting the first sensed current signal so that a value of a vibration of the electric motor is equal to or smaller than a first predetermined value when the motor rotation speed signal is a first rotation speed, and the second offset value being a current value for correcting the first sensed current signal so that the value of the vibration of the electric motor is equal to or smaller than a second predetermined value when the motor rotation speed signal is a second rotation speed.

Steering device

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

A motor is contained in a motor container space. A controller is contained in a controller container space. The motor container space and the controller container space are arranged in series in a direction of a rotation axis of a motor shaft, while interposing a partition wall therebetween. The motor shaft is inserted in a motor shaft through-hole of the partition wall. A magnet is disposed at an end of the motor shaft, in the controller container space. A rotation sensor is disposed in the controller container space oppositely to the magnet, for monitoring a rotational position of the motor shaft on the basis of variation in magnetic field due to rotation of the magnet. A cover made of nonmagnetic metal is disposed between the magnet and the rotation sensor so as to cover the motor shaft through-hole.

Actuator for in-vehicle unit

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

A motor driving device controls driving of an inverter device, detects current values in two phases, and compensates a value. The motor driving device detects current values in two phases, namely, a maximum phase current value and a minimum phase current value, within a single cycle of a PWM carrier frequency. The motor driving device compensates a value obtained by subtracting an absolute value of a difference between two absolute values, namely, the detected maximum phase current value and minimum phase current value, from the smaller value of the absolute values, as the offset current component.

Inverter driving device, electric brake apparatus, and electric power steering apparatus

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

An objective of the present invention is to improve current detection accuracy and to reduce noise of carrier frequency. A motor apparatus and a motor drive apparatus calculate motor currents Iu, Iv, and Iw using a DC bus current detected value Idc of an inverter and control a magnitude and a phase of an applied voltage of a motor to drive the motor. A carrier adjuster decreases a carrier frequency Fc of the inverter if a motor output is relatively larger and that increases the carrier frequency Fc of the inverter if the motor output is relatively smaller. A pulse shift adjuster shifts an interphase waveform of a PWM pulse according to the carrier frequency Fc.

Inverter apparatus

The present invention performs pulse shift control in such a manner that a difference between switching timings of PWM duty signals can reach or exceed a second predetermined value when the difference between the switching timings of the PWM duty signals of phases falls below the first predetermined value, and determines a correction amount for the phase by the pulse shift control in such a manner that a correction amount after switching becomes smaller than a correction amount before the switching of a phase on which the pulse shift control is performed in pulse shift phase switching control.

Motor control apparatus and power steering apparatus

An electrically driven power steering system is capable of reducing development of a noisy magneto-strictive sound. A voltage corresponding to each PWM pulse achieving time corresponding to a hysteresis is added to one of the voltage command values of a large voltage phase from among three phase first voltage command values. The added voltage is subtracted from one of the remaining voltage command values, which is a voltage small phase, to derive virtual voltage command values, and the virtual voltage command values are mutually compared to carry out a voltage magnitude phase determination for a three-phase brushless motor of the power steering system.

Growing community of inventors

Novi, MI, United States of America

Masaki Kashima