Disclosed is a one-phase short-circuit fault-tolerant direct torque control method for a five-phase permanent-magnet motor. When phase A experiences an open-circuit fault, a non-faulty phase open-circuit fault-tolerant current, a fault-tolerant transformation matrix T4/2, and an inverse matrix T2/4 for a fault-tolerant operation of the motor are deduced on the basis of the constraints of the flux vector of a stator remaining unchanged before and after a fault, the sum of the currents of non-faulty phases being zero, and minimal copper consumption; when phase A experiences a short-circuit fault, a remaining non-faulty phase compensation flux linkage is deduced on the basis of the constraints of the flux vector of a stator remaining unchanged before and after a fault, the principle of minimal copper consumption or non-faulty phase compensation currents being equivalent in terms of amplitude, and the sum of remaining non-faulty phase compensation currents being zero; and a stator phase voltage instruction is derived by combining a stator flux linkage with a torque observer, a rated torque and a stator flux linkage amplitude, and a coordinate transformation. The voltage combines a pulse width modulation technique based on zero-sequence voltage injection to implement consistent steady-state performance and dynamic performance before and after a motor short-circuit fau moreover, the frequency of an inverter switch is constant, and the overhead for a CPU is low.
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