Nonlinear field oriented control of induction motors using the backstepping design

Using backstepping, which is a recursive nonlinear design method, a novel approach to control of induction motors is developed. The resulting scheme leads to a nonlinear controller for the torque and the amplitude of the field. A combination of nonlinear damping and observer back-stepping with a simple flux observer is used in the design. Assuming known motor parameters the design achieves stability with garanteed region of attraction. It is also shown how a conventional field oriented controller may be obtained by omitting parts of the nonlinear controller.