Design and Analysis of a Hybrid Stepping Motor for Aerospace Applications

Due to small step size, high positioning accuracy and high reliability, the hybrid stepping motor (HSM) is widely used in aerospace. In this paper, a HSM with improved torque density is designed and investigated for solar array drive assembly. Firstly, the topology and operating principle of the HSM are analyzed. The theoretical equation is derived, the comprehensive design principle is studied, the design method is presented, and the structure parameters are obtained. Then, the electromagnetic and temperature performances are analyzed based on the 3-D finite element method (FEM). Secondly, an axial-radial magnetic circuit transformation equivalent method is proposed to improve calculation speed. Then, the main electromagnetic performances based on 2-D and 3-D methods are comparatively analyzed. Finally, a HSM product is experimented. Compared with the 3-D FEM, the calculation efficiency is increased while the accuracy is maintained by the 2-D method, which validate the correctness of the design scheme. Meanwhile, the high reliability and improved torque density are achieved in the HSM.