Abstract: 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.

Abstract: In a differential operation or a phase lead operation in a control unit for an electric power steering apparatus, by using the differential operation or the phase lead operation utilizing a decimation, noises are exclusively eliminated from information such as the road information detected by a sensor or the like, so that no vibration due to the noises can be caused in a motor output thereby to provide the electric power steering apparatus having neither any handle noise nor any vibration uncomfortable to the driver.

Abstract: 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.

Abstract: 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?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.

Abstract: 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.

Abstract: An initial abnormality analysis data is reliably retained by a controller of an electric power steering apparatus.

Abstract: 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.