Fault-tolerant control strategy for five-phase permanent magnet synchronous motor

Aiming at the open-circuit fault in stator windings for multi-phase motor drive system, this paper proposes an effective fault-tolerant current control strategy. From the perspective of vector space decomposition, the coordinate transformation matrixes under fault conditions were determined and the decomposition mathematical models of five-phase permanent magnet synchronous motor (PMSM) with one-phase winding open were set up. According to the stator copper loss equation at synchronously rotating coordinate system, the vector control methods could be realized by setting the current references in Z₁-Z₂ subspace with different constraints. The experimental results show that the proposed control strategy can reduce the torque ripple caused by the open-circuit fault in stator windings, improve the running performance of five-phase PMSM under fault condition, and enhance the reliability of the governing system.