Trw Limited

Trw Automotive Gmbh

Timothy Sworn

Russell Wilson-Jones

James Owen Patrick Farrelly

Andrew Dennis Barton

Keiwan Kashi

Birk Junghanns

Chris Mantjios

Geoffrey Tullener

Andrew James Pick

Mario Eden

A method of controlling an electric motor of a power steering system having at least three windings is described, wherein a control unit applies a current to the windings of the electric motor to generate a total torque having a value which is ascertained by the control unit from a set-point torque for steering assistance and a set-point torque for damping. A damping set-point circuit ascertains the set-point torque for damping and a steering assist set-point circuit ascertains the set-point torque for steering assistance. A monitoring circuit monitors the function of the windings of the electric motor. In the event of a malfunction of any of the windings, the monitoring circuit outputs an error signal, upon which the set-point torque for steering assistance is reduced.

Method of controlling an electric motor of a power steering system, and power steering system

An electric power assisted steering system comprises a torque sensor, a motor connected to a part of the steering system to provide motor torque to the steering system and a motor controller which is adapted to receive an output signal from the torque sensor and to generate a motor torque demand signal indicative of the torque to be applied by the motor to the steering system. The motor torque demand signal comprises a driver demand component dependent upon the torque applied by the driver; and a diagnostic component independent of the torque applied by the driver and which varies in value over time in a predetermined manner. The system further comprises a monitor that correlates the diagnostic component with the output signal and generates a signal indicating that the output signal is faulty if the correlation falls outside of a predefined range.

Electric power steering system

A road vehicle steering system which is adapted to use measurements and estimates characterising the motion of and forces acting on the vehicle and the steering system such as to derive an estimate of steering system disturbance force and to then use the latter estimate to establish a torque demand for the vehicle electronic power steering (EPS) which substantially compensates for this disturbance force.

Rack force disturbance rejection

Growing community of inventors

Birmingham, United Kingdom

Timothy Sworn