Design and Analysis of Low-Cost Tubular Fault-Tolerant Interior Permanent-Magnet Motor

Tubular motors are suitable for active vehicle suspension due to their zero net radial force and volumetrically efficient. This paper proposes a new low-cost tubular fault-tolerant (TFT) interior permanent-magnet (IPM) motor for the high reliability operation of the active vehicle suspension system. The key is that the proposed motor incorporates the concept of fault-tolerant teeth to provide the desired decoupling among phases and adopts the ferrite magnet material to reduce the usage of rare-earth PMs. Its electromagnetic performances are investigated, such as flux linkage, back electromotive force, mutual- and self-inductances, and detent and thrust forces. A finite-element method is employed to verify the theoretical analysis, showing that the proposed TFT PM motor not only has the merits of low-cost, strong mechanical integrity, but also offers good fault-tolerant ability and high thrust force capability.