A robust adaptive controller for Surface-Mount Permanent Magnet Synchronous Machines

High torque density and the potential for high efficiency have made Surface-Mount Permanent Magnet machines an attractive option for many high-performance drive applications. However, parameter variations due to temperature changes, skin effect, and magnetic saturation, can detune the transient characteristics of the drive, and cause large mismatches in torque regulation. The approach presented in this paper utilizes a combination of adaptively tuned feedforward and feedback-decoupling terms, in addition to standard proportional feedback for added robustness. The resulting controller achieves consistent transient response characteristics with zero steady-state error over a wide range of operating points, without the use of integral control. The adaptive law is derived using Lyapunov´s stability theorem, and the resulting adaptive controller is tested numerically in Simulink. Experimental results confirm the performance of the proposed adaptive controller.