Adaptive nonlinear control of variable reluctance stepper motors

Adaptive nonlinear control of variable reluctance motors is considered in this paper. Using backstepping techniques, a controller is designed that is robust to parametric and dynamic uncertainties. The disturbances are assumed to be bounded by polynomials in the states. A commutation strategy is applied to define desired currents that would produce the desired torque signals. These desired currents then become the tracking objective for the electrical subsystem. The overall stability of the system is shown using Lyapunov techniques. The tracking errors are shown to be globally uniformly bounded.