For a long time, the control of electrical drives has been dominated by analog technology. During the last two decades, with the developments of microprocessors and peripheral circuits (memory, data converters, timers, . . .), digital technology has gradually replaced analog technology in conventional control functions and allowed the implementation of advanced control functions previously unattainable. Today, digital technology is considered as the sole and unrivaled approach for high-performance advanced motion control systems because of the unique possibilities it can offer.