Analysis and inhibition of disturbing torque in gimbal servo system of SGCMG

The gimbal servo system based on the brushless DC motor (BLDCM) as the driver of Single Gimbal Control Momentum Gyroscopes (SGCMGs) is built up by Simulink in this paper firstly. And the mathematical expressions of three types of disturbing torque which are involved torque between the gimbal axis and satellite, ripple torque of the BLDCM, and friction torque acting on the gimbal axis are derived from the prototype of SGCMG in our lab. The traditional control law can not restrain the uncertain or immeasurable disturbing torque effectively, so the adaptive compensation control strategy is put forward to eliminate the involved torque and the friction torque, and adding the variable overlapped commutating time into the circuit loop can restrain the ripple torque. The results of experiments show that the control law can restrain the disturbing torque effectively.