Flatness based sliding mode controllers for a drive system consisting of an asynchronous machine with a cage rotor and a two-level converter are in the focus of this thesis. The controllers are designed by using a backstepping approach in order to ensure the tracking of nominal trajectories. These trajectories are planned in such a way that limitations of the system are taken into account. An additional key point consists in the study of algebraic methods to identify the rotor flux linkage and the load torque. Furthermore, flatness based controllers for two other applications are studied. The first one is a three-level neutral-point-clamped converter connected to the grid. The second one is a drive system consisting of an asynchronous machine with a cage rotor and a three-level flying-capacitor converter.