Adaptive-backstepping-based design of a nonlinear position controller for an IPMSM servo drive

This paper presents the design of a novel nonlinear position controller for an interior permanent-magnet synchronous motor (IPMSM) servo drive. The motor model equations provide the basis for the proposed controller, which is designed with the adaptive backstepping technique. Various system uncertainties, particularly mechanical-parameter uncertainties, are incorporated in the design of the controller. Using Lyapunov´s stability theory, it is verified that the control variables are asymptotically stable. The complete drive system is then simulated with MATLAB/Simulink software. Performance of the proposed adaptive-backstepping-based nonlinear position controller (ABNPC) is investigated under different dynamic operating conditions such as step changes in command positions, step changes in load, and parameter variations. The results indicate that the proposed ABNPC-based IPMSM drive could be a candidate for real-time industrial servo motor drive applications.