Mitsubishi Electric Corporation

Mitsubishi Denki Kabushiki Kaisha

Katsuya Ikemoto

Shunichi Wada

Takayuki Yamamoto

Masaki Matsushita

Ryoichi Yonezawa

Chiaki Fujimoto

Yasuaki Hori

Takayuki Kifuku

Hiroyuki Kozuki

Takahiro Okanoue

Masayuki Maruyama

Kenta Kawahara

Hideki Doi

Eiji Iwami

Mamoru Shiraki

Provided is an electric power steering device including a phase compensation unit having a desirable phase compensation characteristic for each vehicle speed region, which suppresses deterioration in stability of a steering system in a case where the phase compensation characteristic is changed to a different phase compensation characteristic, in which the phase compensation unit includes: a plurality of phase compensation calculation units configured to execute phase compensation calculation based on each phase compensation characteristic; a phase compensation characteristic determination unit configured to determine a phase compensation characteristic based on a vehicle speed signal output from a vehicle speed sensor; and a selection unit configured to select a phase-compensated torque signal output by the phase compensation unit from phase compensation calculation results output by the plurality of phase compensation calculation units in consideration of an amount of change in phase compensation calculation result at a time of switching the phase compensation characteristic.

Electric power steering device and control method therefor

A malfunction detection device for a resolver detects malfunction in a resolver with accuracy and stability even if a value of a square sum is varied between inside and outside of a normal range. When the resolver is in malfunction, a sine signal and a cosine signal are read. It is determined whether a malfunction determination of the resolver is prohibited, or not, from read values of the sine signal and the cosine signal, or square values thereof. When it is determined that the malfunction determination of the resolver is prohibited, the count value is accumulated and incremented every time the test value falls outside a normal range. When the count value arrives at a given value or higher, it is determined that the resolver is in malfunction.

Malfunction detection device for resolver

In a CPU () for calculating a control amount of an electric power steering control apparatus including a motor for assisting a steering force of a steering wheel generated by a driver of a vehicle, a filter section () subjects a value of a motor rotation speed calculating section () for calculating an rotation speed of a motor () to filter processing, to thereby output the resultant value to a target d-axis current value setting section (). With this configuration, in a high-torque and high-motor-rotation speed region, responsiveness of a target d-axis current value with respect to the motor rotation speed is decreased, to thereby suppress vibrations and noise when the steering wheel is operated.

Electric power steering control apparatus and steering control method

A resolver device () includes: a microcomputer () for outputting a control signal for driving a motor () to a drive circuit (); a sensor section () (resolver) for outputting detection values (a sine signal and a cosine signal) in accordance with a rotation angle of the motor (); and a signal circuit () provided between the microcomputer () and the sensor section (). The microcomputer () determines an abnormality when the detection values of the sensor section () are out of a first normal range and then determines return of the sensor section () to normal when the detection value is present within a second normal range and in a plurality of regions obtained by dividing the first normal range.

Resolver device, motor control device, and motor control method

An object is to provide a specific achievement means for achieving reliable failure determination in a control system in a motor control device. The motor control device includes motor drive means for supplying a motor current to a motor; motor current detection means for detecting the motor current; and a controller to which a motor current detection value from the motor current detection means is input, and which outputs a drive signal to the motor drive means, in which the controller includes voltage control means for controlling a voltage applied to the motor; power supply voltage detection means; means for limiting the maximum value (%) of a drive duty ratio in a PWM circuit to a smaller value, upon determining power supply voltage drop; and failure determination means for determining a failure in a case of an abnormal motor current value.

Motor control device

A main microcomputer abnormality determination section checks whether or not a voltage value of Vcc based on digital data output from a main microcomputer analog-to-digital converter is equal to or higher than a threshold value to thereby perform abnormality determination for the main microcomputer analog-to-digital converter and Vref. A sub microcomputer abnormality determination section checks whether or not the voltage value of Vcc is equal to or higher than a threshold value based on digital data output from a sub microcomputer analog-to-digital converter to thereby perform abnormality determination for the sub microcomputer analog-to-digital converter and Vref. An abnormality identifying section identifies an abnormality occurring site by using both results of the abnormality determination performed by the main microcomputer abnormality determination section and the sub microcomputer abnormality determination section.

Electronic control device

An electric power steering equipment according to the present invention comprises a motor for providing a steering assisting force to a steering shaft, a torque detecting means for detecting a steering torque, an amplifying and phase-compensating means for amplifying and phase-compensating a detected value of the torque detecting means, and a controlling means for controlling a drive of the motor based on an output of the amplifying and phase-compensating means, wherein the controlling means restricts a control signal for driving the motor by an upper limit value and a lower limit value which are set in response to the detected value of the torque detecting means.

Electric power steering equipment

Even when a vehicle is rapidly decelerated, an electric power steering apparatus can provide a steering torque corresponding to such a deceleration of the vehicle, so that the vehicle can be steered in a stable manner without a steering wheel being adversely influenced by road surface irregularities. The apparatus includes a vehicle speed detecting unit for detecting a speed of the vehicle, a torque detecting unit for detecting steering torque, a deceleration calculating unit for calculating a deceleration of the vehicle from the vehicle speed detected by the vehicle speed detecting unit, a first assist force calculating unit for calculating a first assist force from the detection results of the vehicle speed detecting unit and the torque detecting unit, a second assist force calculating unit for calculating a second assist force in response to the deceleration calculated by the deceleration calculating unit, and a control unit for applying to the steering system an assist force which is a sum of the first assist force calculated by the first assist force calculating unit and the second assist force calculated by the second assist force calculating unit.

Electric power steering apparatus

To provide an electric power steering apparatus that is superior in operationability and reliability and is capable of keeping stable steering feeling by automatically compensating the torque reference value. The electric power steering apparatus is provided with a steering torque detecting Mmeans for detecting a steering torque to be applied to a steering system of a vehicle, a vehicle velocity detecting Mmeans for detecting a vehicle velocity of the vehicle, a curvature radius calculation Mmeans for calculating a radius of curvature of a road along which the vehicle travels, a torque reference value storage Mmeans for storing a torque reference value of the steering torque, a torque compensation Mmeans for compensating the torque reference value of the steering torque on the basis of the steering torque detected by the steering torque detecting Mmeans in response to the detected vehicle velocity and the detected radius of curvature, a compensation controlling Mmeans for calculating an inferential steering torque on the basis of the torque reference value obtained by the torque compensation Mmeans and the detected steering torque, and a target current setting Mmeans for setting a target current on the basis of the vehicle velocity and the inferential steering torque.

A vehicle position recognition apparatus comprising one or a plurality of magnetic field formation means 1-1 installed at predetermined positions on a road for forming a predetermined magnetic field, magnetic field strength detection means 1-4 for detecting the magnetic field formed by the magnetic field formation means 1-1, vehicle position computation suitability judgment means 1-5 for judging whether the magnetic field strength, obtained by the magnetic field detection means 1-4, is suitable or not for computing a position of the vehicle, and vehicle position computation means 1-6 for receiving a result of the judgment of the vehicle position computation suitability judgment means 1-5 and for detecting the position of the vehicle by the magnetic field strength detected by the magnetic field strength detection means 1-4.

Growing community of inventors

Tokyo, Japan

Katsuya Ikemoto