Abstract: An electric power steering apparatus that performs an assist control of a steering system, including: at least two respectively independent torque sensors and angle sensors, wherein having a function that respectively calculates steering angles from the torque sensors and the angle sensors to utilize, wherein comparison diagnoses of independent signals are performed and also concurrently individual diagnoses of each individual signal are performed, in a case that it is judged that there is an abnormality in the comparison diagnoses, the angle sensor signals are not used, in a case that it is judged that at least one of the individual diagnoses is abnormal, the angle sensor signal is treated as downgrading, and in a case that it is judged that two or more of the individual diagnoses are abnormal, the angle sensor signals are not used.

Abstract: An electric power steering apparatus that performs an assist control of a steering system, including: at least two respectively independent torque sensors and angle sensors, wherein having a function that respectively calculates steering angles from the torque sensors and the angle sensors to utilize, wherein comparison diagnoses of independent signals are performed and also concurrently individual diagnoses of each individual signal are performed, in a case that it is judged that there is an abnormality in the comparison diagnoses, the angle sensor signals are not used, in a case that it is judged that at least one of the individual diagnoses is abnormal, the angle sensor signal is treated as downgrading, and in a case that it is judged that two or more of the individual diagnoses are abnormal, the angle sensor signals are not used.

Abstract: An electric power steering apparatus having a function for detecting a steering speed, includes a time stamp attaching section that attaches a time stamp (ATi) to a detection signal (Ai) and attaches a time stamp (BTj) to a detection signal (Bj); a storing section that stores the detection signal (Bj) to which the time stamp (BTj) is attached; a synchronous signal searching section that searches the detection signal (Bj) most synchronized with the detection signal (Ai) based on the time stamps (ATi and BTj); a vernier calculating section that performs a calculation of an angle difference between synchronous signals searched by the synchronous signal searching section and a vernier calculation and outputs an absolute steering angle of a sensor reference; an initial steering angle calculating section that calculates an initial steering angle value from the absolute steering angle; and a steering angle output section that obtains a steering angle.

Abstract: An electric power steering apparatus having a function for detecting a steering speed, includes a time stamp attaching section that attaches a time stamp (ATi) to a detection signal (Ai) and attaches a time stamp (BTj) to a detection signal (Bj); a storing section that stores the detection signal (Bj) to which the time stamp (BTj) is attached; a synchronous signal searching section that searches the detection signal (Bj) most synchronized with the detection signal (Ai) based on the time stamps (ATi and BTj); a vernier calculating section that performs a calculation of an angle difference between synchronous signals searched by the synchronous signal searching section and a vernier calculation and outputs an absolute steering angle of a sensor reference; an initial steering angle calculating section that calculates an initial steering angle value from the absolute steering angle; and a steering angle output section that obtains a steering angle.

Abstract: An electric power steering apparatus includes motor relative angle detect means 48 including motor relative angle information calculating portions 48a ˜48c for calculating the relative angle information of an electric motor corresponding to a driver's steering amount applied to a steering system and a relative angle information compensating portion 48e for preventing the motor relative angle information calculating portions from being incapable of obtaining the relative angle information to thereby enable to generate the relative angle information all the time. The motor control means controls the electric motor based on arbitrary actual angle without setting an initial angle at the time of driving based on the relative angle information detected by the motor relative angle information detection means. It is restricted to impart uncomfortable feeling on the driver by using simply configured motor rotation angle detection means which prevents from increasing of the number of parts and cost.

Abstract: A electric power steering apparatus having a steering torque detecting unit for detecting a steering torque transmitted to the steering system; an electric motor for generating a steering assist force to give to the steering system; a motor control unit for controlling the electric motor based on at least the steering torque. The apparatus comprises a motor stop condition detecting unit for detecting a condition to stop the electric motor while the electric motor is under control by the motor control unit; and an electromagnetic brake control unit over the electric motor in order to suppress a kick-back based on at least either one of a steering condition of the steering system and a running condition of the vehicle when a detection result by the motor stop condition detecting unit shows that a condition occurs to stop the electric motor.

Abstract: The present invention provides a high-performance control unit for an electric power steering apparatus structured such as to improve a steering feeling at a time of a control stop of the control apparatus by calculating a steering torque correction short-amount without stopping a function of a motor control signal monitoring means and applying an electromagnetic brake to the motor in correspondence to the steering torque correction short-amount even in the case of stopping a motor control during generation of a steering assist torque, lighten a load applied to a driver due to a rapid release of a tire torsion force at a time of stopping the assist, and prevent a driver from feeling an uncomfortable feeling.

Abstract: An electric power steering apparatus includes a first torque command value calculating means that calculates a first torque command value on the basis of steering torque detected by a steering torque detecting means, a malfunction torque detecting means that detects malfunction of the steering torque detecting means, and a self aligning torque estimating means that estimates self aligning torque transmitted from a road surface to a steering mechanism, and the apparatus further includes a second torque command value calculating means that calculates a torque command value on the basis of the self aligning torque estimated by the self aligning torque estimating means, and an switching means that selects the second torque command value calculating means.