A new tubular fault-tolerant permanent-magnet motor for active vehicle suspension

The flux-switching permanent magnet (FSPM) motors are a new class of moving-iron machines, offering high power density, simple and robust rotor structure, and good thermal dissipation conditions. This paper proposes a new tubular fault-tolerant FSPM (TFT-FSPM) motor for high reliability operation of the active vehicle suspension system. The key is that the new motor topology incorporates the concept of fault-tolerant teeth to provide the desired decoupling among phases. Two TFT-FSPM motors, viz., the existing and the proposed ones, are designed based on the size constraints of the vehicle suspension. They are compared in terms of their flux linkages, back-EMFs, self and mutual inductances as well as cogging and thrust forces. The finite element analysis results show that the proposed TFT-FSPM motor not only retains the merits of high power density, strong mechanical integrity, good immunity from thermal problem and high thrust force capability, but also offers higher performances and lower cost than the existing one.