An on-load tap changer is provided having a plurality of modules, each of which is operable to change taps in a winding of a transformer. A transmission shaft is connected to the modules and is operable upon rotation to effectuate tap changes in the windings. A servo motor rotates the transmission shaft. The servo motor includes a feedback device operable to generate a feedback signal containing information relating to the position of the motor shaft. A servo drive is connected to the servo motor to receive the feedback signal. The servo drive uses the feedback signal to determine and store a total angular displacement of the motor shaft. The servo drive uses the feedback signal and the total angular displacement of the motor shaft to control the operation of the servo motor.