Development of a slotless limited-angle torque motor for reaction wheels torque measurement system

This paper presents a novel slotless limited-angle torque motor (LATM) for reaction wheels torque measurement system. The proposed slotless LATM has a uniform torque profile during its operating range, constant torque coefficient owing to avoiding saturation in back iron core. The slotless LATM has been designed and optimized using both magnetic circuit method and 2-D FE method. A scheme of magnetic pole spliced by three segments is proposed to improve flat width of air-gap flux density and torque performance. Finally, a prototype machine is established and its experimental results are presented and discussed. The theoretical and numerical results are validated with the experiments in the same operating conditions.