Optimal design and remedial control of fault-tolerant permanent magnet motors

Abstract

Fault-tolerant Permanent Magnet (PM) motors are good candidates for Electrical Vehicle (EV) applications, offering high power density, high effi ciency and high reliability. This paper investigates optimal design and fault-tolerant control strategy of a four-phase fault-tolerant PM motor with a Halbach PM array, aiming to deal with short-circuit and open-circuit faults, respectively. First, by comparing with a conventional array, the Halbach PM array is evaluated for the fault-tolerant PM motor. Second, by optimising the stator tooth shape, the short-circuit current is limited. Third, by doubling the current of the healthy phase, a remedial control strategy for the open-circuit fault is proposed. The predicted results of the motor’s performance are based on the finite element and co-simulation methoDs. Measurement results from tests on a laboratory prototype are used to verify the theoretical analysis.