This paper mainly expounds the basic theory of motor fault-tolerant control, research for the current control strategy under single-phase open-circuit fault of the permanent magnet synchronous motor, adopting the finite element analysis software to simulate and calculate for permanent magnet synchronous motor model. Put emphasis on the research on output torque under abnormal state of running by the use of fault tolerant control strategy for the motor. The simulation result shows that the running performance of motor can still be ensured when the motor running in lack of phase or in asymmetric cases. This paper provides new ideas for reference for high precision and high efficiency control of permanent magnet synchronous motor.