A composite controller strategy for electromechanical actuator using a permanent-magnet synchronous motor

Considering the uncertainties parameters and unknown dynamics of permanent-magnet synchronous motors in real applications, a composite controller strategy for electromechanical actuator is proposed in this paper. The composite strategy consists of a disturbances observer based on linear extended state observer that suppresses disturbances by feedforward compensation and a Lyapunov stability-based position controller. A non-singular terminal sliding mode position controller is used here due to its good performance, under which state errors would converge to zero in finite time. Besides, special forms of load torque, hinge moment, and sinusoidal torque disturbances have been taken into consideration in this paper. The proposed control strategy is verified via simulation. High performance with respect to position tracking and robustness to load disturbances and parametric uncertainties of the motor have been demonstrated.