A method for controlling an electrical power steering system for a vehicle
includes an electrical servomotor, a steering device for entering a
reference value (.theta..sub.S) of a steering angle into a control andlor
regulation device, a moment sensor and an angle sensor for the steering
device, a device for estimating the moment (M.sub.v) at the steering
device and an angle sensor for determining the angle (.theta..sub.A) of a
power take-off of the electrical servomotor. In order to control the
electrical power steering system, which makes a non-critical behavior
possible in the event of a malfunction or failure of a moment sensor at
the steering device, provisions are made so that an offset value
(.DELTA..sub..theta.) is constantly formed from the reference value
(.delta..sub.S) of the steering angle and the actual value .theta..sub.I
of the steering angle, and a virtual moment (M.sub.v) of the steering
device is determined on the basis of the offset value
(.DELTA..sub..theta.) and is used to control the electrical servomotor.