To meet the technical requirements of high fault tolerance and excellent electromagnetic performance for automotive steering motors

a modular steering motor topology with both electrical isolation and favorable magnetic isolation characteristics between unit winding modules was proposed. This topology can ensure that the motor maintains high output power and operational performance even under light fault conditions. First

the fault-tolerant mechanism of the modular motor was elaborated

and the main types of winding open-circuit faults were classified. Second

the influence mechanism of the number of open-circuited phases on the motor output torque was analyzed

the internal cause of increased torque ripple induced by faults was revealed

and verification was conducted via the finite element method(FEM). Third

aiming at typical open-circuit fault types

a targeted fault-tolerant control strategy was proposed

and the fault-tolerant current expression was derived. The derived current can effectively suppress the dominant harmonic components in the torque and significantly reduce torque ripple. Finally

an experimental platform for the modular steering motor was established to verify effectiveness and feasibility of the proposed fault-tolerant control strategy through experiments. The results demonstrate that the proposed topology and control strategy can significantly improve the operational stability of the motor under fault conditions

and provide theoretical and experimental support for the fault-tolerant design of automotive steering motors.