Design and Analysis of a Five-Phase Fault-Tolerant Permanent Magnet Synchronous Motor for Aerospace Starter-Generator System

In this paper, a novel five-phase fault-tolerant permanent magnet synchronous motor (FTPMSM) is designed for aerospace starter-generator (SG) system. Small teeth are placed at the center of the slots, in which the two coils belong to different phases, and on both sides of the small teeth, thermal insulation materials are placed. In this way, the motor owns low thermal coupling and no electromagnetic coupling among different windings. By optimizing the stator size and rotor structure, the short-circuit current is limited to a low level and thus the motor has strong fault-tolerant capability under short-circuit fault. The finite element analysis (FEA) model of the five-phase FTPMSM is established, by which no-load characteristic, load characteristic, and fault-tolerant capability of the motor are analyzed. The simulation results show that the mutual inductance of different phase windings are almost zero, and the motor has good fault-tolerant capability. Finally, the prototype of the proposed five-phase FTPMSM is built to verify the design and simulation results.