I. Introduction
Depending on the motor design, harmonics occur in many electrical machines phase currents. They consume power that does not generate torque. In field oriented control, the alternating phase currents are converted into direct signals. Harmonics result in an alternating component within these direct signals. Since the alternating component is periodically cyclic to one electrical rotation, it can be eliminated by an iterative learning control. With the iterative learning control, periodically cyclic errors can be eliminated by storing and processing the error of the last period. The error thus becomes smaller with each period. Iterative learning control can be used in various applications. In previous publications, it has been used for a 50 Hz load emulation system [1] to compensate harmonics in the grid currents. Furthermore, iterative learning control was used to improve a repeated cyclic process for an injection unit of a plastic injection molding machine [2].