Patent ID: 6496762
Filing Date: 2002-12-17
Classification: B62D

Abstract:
An electric power steering controller mounted on a vehicle and using torque generated by an electric motor to supplement a driver's steering torque, said electric power steering controller comprising:an electric motor; steering torque detection means for detecting steering torque applied by a driver to a steering wheel; steering angle detection means for detecting a steering angle; first road reaction torque estimation means for estimating a first road reaction torque that tires of the vehicle receive from a road surface using the steering torque detected by said steering torque detection means; second road reaction torque estimation means for estimating a second road reaction torque using the steering angle detected by said steering angle detection means; and returning torque compensation means for controlling an assisting torque produced by said electric motor in a direction to return the steering wheel to an original position according to the second road reaction torque estimated by said second road reaction torque estimation means, said returning torque compensation means determining that said steering angle detection means has a fault when a difference between the first road reaction torque and the second road reaction torque is greater than a given value.