Digital robust speed servo system with complete avoidance of output saturation effect

In order to prevent a robust speed servo system from having the saturation effect of controller output, this paper proposes a new anti-windup algorithm for a robust high-order speed controller connected to PI current controller in series. Using the proposed algorithm, a digital speed servo system completely avoids having the effect of output saturation caused by the limitation of motor voltage and motor current. The experimental results show that the proposed digital speed servo system has no output saturation effect caused by the limitation of motor voltage and motor current. The proposed system keeps the desired speed response for a fast and large speed reference on condition of full load torque