Research of the flywheel motor driver in satellite attitude control system

This paper proposes a novel control system for brushless DC motor which is applied to reaction flywheel. Reaction flywheel is the execution unit of satellite attitude control system. The attitude stability and the control precision of the satellite system is determined by the performance of the motor control system. With torque control mode, a novel bridge type inverter and dual-PWM method are adopted. The proposed inverter, in which the motor windings are independent from each other, eliminates the negative effects of common-mode voltage and differential-mode dv/dt. The negative effects are caused by the high dv/dt switching of the conventional three phase bridge inverter. Dual-PWM method adopts the double closed-loop current controlling scheme which includes bridge-arm voltage pulse amplitude modulation and winding current pulse width modulation. The scheme reduces the torque jumping which is caused in braking at a high speed state with PWM method in application. Experimental results show that the proposed control scheme has less torque jumping in braking and better dynamic characteristics