Nsk Corporation

Nsk Steering Systems Co., Ltd.

Yuho Aoki

Shuji Endo

Kenichi Okamoto

Kazuhiro Kumaido

Kenji Mori

Toru Sakaguchi

Hideyuki Kobayashi

Hideaki Kawada

Yusuke Itakura

CaoMinh Ta

Atsushi Horikoshi

Sakae Nejo

Lilit Kovudhikulrungsri

Tetsuro Otsuka

Hideaki Okazaki

Nobuhiro Kubo

Kenji Arai

An in-vehicle electronic control device for diagnosing the details of an abnormality of a microcomputer appropriately is provided. A monitoring function for detecting a malfunction by monitoring input/output of a main function of a hardware part and a monitoring function for detecting an abnormality by monitoring the calculating result of a main function in a software part are provided in a microcomputer. The main function to be monitored is implemented with a different structure than the malfunction/abnormality monitoring function. Furthermore, a malfunction processing circuit for monitoring an abnormality of the microcomputer is provided outside the microcomputer.

In-vehicle electronic control device

The present invention provides a controller of an electric power steering device which does not apply an uncomfortable feeling to a operation of steering wheel while securing a fault determination confirming period enough long to prevent an erroneous detection of a torque sensor fault, and can secure a safety operation of steering wheel, even in the case that an output value of a torque sensor detecting a steering torque of a steering wheel becomes abnormal.

Controller for electric power steering device

The invention relates to a control apparatus of an electric power steering apparatus structured such as to apply a steering assist force generated by a n-phase motor to a steering system of a vehicle, the control apparatus is provided with at least (n&#x2212;1) numbers of current detecting means for detecting a current Im in each of phases of the motor, a current command value calculating means for outputting a current command value Imref in each of the phases, and n numbers of current control means, and the control apparatus executes a current control of each of the phases by the current control means having the current command value Imref in each of the phases and the current Im in each of the phases as an input.

Control apparatus of electric power steering apparatus

The present invention includes a control part for controlling switching elements on diagonal lines in the upper and lower stage of an H bridge circuit respectively by different duty ratios based on a steering torque exerted on a steering system, and an electric power supply source for supplying an electric power. When the voltage of the electric power supply source is lower than a prescribed voltage, the control part causes the switching element EETor FETon the upper-stage side to be driven by a pulse width modulation signal PWMor PWM, the switching element FETor FETon the lower-stage side to be turned on, and the frequency of the pulse width modulation signal to be lowered to an audible frequency range.

Electric power steering device

In the present invention, only an abnormality of detection of a rotating direction of a motor is detected and therefore, with simple processing and by using a table for judging the abnormality of the detection of a rotating direction of a motor and the rotating direction of the motor, the abnormality of the detection of a rotating direction and the rotating direction of the motor are judged at one time.

Control unit for electric power steering apparatus

In order to solve a problem that a motor generates a noise so as to deteriorate an environment in a vehicle if a field weakening control is executed to the motor of a electric power steering apparatus, in the case that a vehicle speed is high, the same field weakening control as the conventional one is applied to the motor because a noise generated due to a friction between a tire and a road surface and a wind noise of a vehicle body are large, and in the case that the vehicle speed is low, the field weakening control is weakly applied in comparison with the conventional one because the noise generated by the motor is felt relatively largely. Accordingly, the field weakening control can be executed in response to the vehicle speed in such a manner as to make the motor noise smaller.

Since an abnormality is judged by executing a square calculating process with respect to sin &#x3b8; and cos &#x3b8; for detecting an abnormality in an angular resolver, a processing time is elongated, and a burden to a CPU is great. Since the invention prepares a map which can judge whether the combination of sin &#x3b8; and cos &#x3b8; is normal or abnormal, and judges by mapping the combination of the detected sin &#x3b8; and cos &#x3b8;, a process can be easily executed, a processing speed is high, and a burden to the CPU can be reduced. Further, an assist can be maintained by controlling a motor by a rectangular wave current by detecting a rotation angle signal at low resolution level, such as Hall sensors arranged around the motor.

An initial abnormality analysis data is reliably retained by a controller of an electric power steering apparatus. The controller of the electric power steering apparatus is constituted by comprising abnormality detection device for detecting the abnormality of a steering assist control mechanism comprising an electric motor giving a steering assist force to a steering system and abnormality data storage device for storing abnormality analysis data in storage device when the abnormality of the steering assist control mechanism is detected by this abnormality detection device, wherein the storage device comprises a plurality of overwrite prohibition storage areas for prohibiting rig the overwrite of the abnormality analysis data and a plurality of overwrite allowable storage areas for overwriting and storing the abnormality analysis data, and wherein the abnormality data storage device stores the abnormality of the steering assist control mechanism detected by the abnormality detection device in the overwrite prohibition storage area when the abnormality is a first abnormality analysis data, and stores the abnormality in the overwrite allowable storage area when the abnormality is the abnormality analysis data subsequent to the second time.

Controller of electric power steering apparatus

The present invention provides an excellent electric power steering apparatus in which torque ripple caused by a quantization error of a current control system generated in case of slow steering state and steering holding state, namely, vibration and noise on a steering wheel can be suppressed. A current controller in which a steady state gain of feedback control is a finite value is used so as to be capable of suppressing the vibration and noise. Further, according to the present invention, a smoothing filter is included in a current control system so that the quantization error is smoothed so that the torque ripple is suppressed.

Growing community of inventors

Gunma, Japan

Yuho Aoki