A method for operating an electric power steering system of a motor vehicle, wherein a steering wheel angle is specified by a steering handle as a measurement for a desired wheel steering angle for at least one steerable wheel of the motor vehicle, wherein an electric servo drive having an electric motor provides steering assistance, and wherein an additional restoring force is provided to compensate for increased internal friction in the power steering system based upon temperature, wherein the additional restoring force is reduced based upon a desired steering direction that is detected at the steering handle. Also disclosed is an associated electric power steering system, an associated computer program, and an associated control unit.

An electric power steering apparatus of a vector control system that drives and controls a motor by an inverter and applies an assist torque to a steering system of a vehicle, including the first compensation function to perform a dead time (DT) compensation based on respective phase motor terminal voltages and respective phase duty command values, the second compensation function to perform a DT compensation based on steering assist command values, the third compensation function to perform the DT compensation based on dq-axis current command values, and a temperature detecting section to detect temperature of ECU, wherein the correction of the DT compensation is performed based on the temperature, wherein switches of the compensation functions are performed by using a conditional branch due to software and a gradual-changing switch, wherein the dq-axis DT compensation values after the conditional branch and the gradual-changing switch are performed are calculated, and wherein the dq-axis voltage command values are compensated by the dq-axis DT compensation values.

A steering apparatus includes: a mechanism that turns a turning wheel; a first motor that generates a driving force that is given to the mechanism; and a control device. The control device includes: a first computation circuit that computes a first limiting value to which an electric current to be supplied to the first motor is limited in a particular situation; a determination circuit that determines whether the turning wheel is in touch with an obstacle; a second computation circuit that computes a second limiting value to which the electric current to be supplied to the first motor is limited when the determination circuit determines that the turning wheel is in touch with the obstacle; and a third computation circuit that computes the threshold to be used by the determination circuit, based on a smaller limiting value of the first limiting value and the second limiting value.

A steering device includes: a mechanism configured to turn turning wheels of a vehicle; a motor configured to generate drive force that is applied to the mechanism; and a controller configured to control the motor in accordance with a steering state. The controller includes a determination circuit configured to determine whether or not one of the turning wheels is in contact with an obstacle based on at least a value of electric current that is supplied to the motor and a vehicle speed. The controller is configured to, when one of the turning wheels is in contact with the obstacle, notify a driver that one of the turning wheels is in contact with the obstacle.

A steering system includes a mechanism configured to turn a steer wheel of a vehicle, a motor configured to generate driving force that is applied to the mechanism, and a controller configured to control the motor according to a steering status. The controller includes a limiting control circuit configured to limit a current that is supplied to the motor to a limiting value, a determining circuit configured to determine whether the steer wheel is in contact with an obstacle by using at least a comparison between a value of the current that is supplied to the motor and a threshold, and a threshold computing circuit configured to compute the threshold that is used by the determining circuit, the threshold computing circuit being configured to compute a value less than the limiting value according to the limiting value as the threshold.

An apparatus for compensating for low-temperature torque of an MDPS including a column torque sensor configured to detect a column torque; a vehicle speed sensor configured to detect a vehicle speed; a temperature sensor configured to measure a temperature of the vehicle; a steering angle sensor configured to detect a steering angle of a steering wheel; and a controller configured to calculate an assist torque, calculate a vehicle speed gain and a compensation gain for the temperature and an accumulated steering angle based on the vehicle speed, the temperature and the steering angle, calculate a final compensation gain by applying a compensation gain attenuation rate, calculate a final assist torque by applying the final compensation gain to the assist torque, and output the final assist torque.

A method operates a steering device which comprises at least one electric motor that can be operated with an increased torque lying between a nominal torque of the electric motor and a maximum torque of the electric motor over an entire basic setting range. In at least one operating state, a threshold torque of the electric motor is at least temporarily limited to a reduced torque, in particular in comparison to the maximum torque, at least depending on at least one temperature characteristic variable.

The vehicle control system is applied as a system of a vehicle mounted with an EPS device having an electric motor driven to control the steering angle. The vehicle control system includes a controller configured to perform steering control for controlling an energization of the electric motor to control the steering angle of the wheels. When the wheels are held after being steered by a specific steering in the steering control, the controller performs a steering return process in which the wheels are turned back and held in a direction opposite to a steering direction of the specific steering. And during a stationary steering-holding in which the steering angle is held and the vehicle is stopped, the controller performs an energization suppression process for reducing energization to the electric motor to be smaller than the energization before the stationary steering-holding.

A method of controlling a motor, for example of an electric power steering system, includes receiving a motor torque demand signal indicative of a torque required from the motor. A current demand signal indicative of the currents to be applied to each phase to meet the torque demand is generated from the motor torque demand signal. One or more operational values from the motor are determined. The current demand signal is set as a function of one or more parameters of the motor obtained by fitting a flux linkage model to the measured operational values. A motor circuit having the permanent magnet electric motor includes a control stage arranged to generate the current demand signal in response to a torque demanded of the motor. A modifying means modifies the magnitude and/or the phase of the current demanded for each phase of the motor by the controller.

To provide a three phase duplexing motor for electric power steering apparatus that can manage increase in a supply current and can manage influence on motor, when increasing a supply current to the three phase windings of the normal set. An three phase duplexing motor for electric power steering apparatus sets 0 to a supply current to three phase winding of abnormality occurrence set, and increases a supply current to three phase windings of the normal set, with a preliminarily set increase upper limit current value as an upper limit.