RESOLVER IN DIGITAL CONTROL LOOP

A digital control loop based on a resolver as feedback device is considered. This technique is popular in NC systems of machine tools. The control circuit transforms a train of pulses generated by a digital interpolator into a phase-modulated command signal and compares it with a phase-modulated feedback signal. The resulting phase-difference is the drive signal to the motor. The principle of the loop is explained, and a mathematical analysis is presented.