Current controlling servo-amplifier for reversible DC steering motor

摘要

A current controlling servo-amplifier system (101) for regulating the MOSFET power transistors (110) and thereby a reversible DC motor (100) which provides the steering torque for the rear-wheels of a FWS motor vehicle monitors the motor counter-emf (124) in relation to its dynamic characteristics, the required control current (130) and the angular position (theta) of the armature confirmed by the sensor (102). A direct measurement of the motor supply voltage (VE) via the MOSFET turn-on ratio (121, 122, 123) enables its correction as referenced by the counter-emf measurement (124) such that a close approximation to an ideal response is obtained including occasions of high motor rpm.