Minimizing the electromagnetic torque fluctuation from measure error based on Kalman filter algorithm compensation

As spacecraft attitude control task becoming more difficult, Control Moment Gyro (CMG) obtained more and more attention, The CMG output torque quality is directly determined by the gimbal motor ultra-low speed fluctuation. The gimbal motor electromagnetic torque fluctuations caused by speed fluctuations can not be ignored, The electromagnetic torque fluctuations which caused by the DC bias and Amplitude imbalance during current measurement stage, that cause motor speed fluctuations, deteriorate the system performance, increased output torque noise of the CMGs. This paper analyzes torque fluctuations, which caused by the sensor DC bias and amplitude imbalance of the current measurement. The harmonic characteristics of the two current sensors and three current sensors were compared. Using the Kalman filter algorithm to be suppressed the harmonic fluctuations, and verification the algorithm based on DSP computer. Experimental results show that, using three current sensors can effectively reduce the electromagnetic torque ripple, and the Kalman filtering algorithm is able to effectively adjust the paranoia and amplitude bias of the current, achieving effective compensation, and reducing the torque ripple.