Design and Analysis of a Novel Tubular High-PM-Utilization Transverse-Flux Linear Machine

Owing to the low permanent magnet (PM) utilization in conventional transverse-flux machines, a novel tubular high-PM-utilization transverse-flux linear machine (HPMU-TFLM) is proposed in this article. The PM utilization ratio of the proposed machine is nearly 100% in theory. Thus, this machine presents a higher power factor and thrust density. First, the basic structure and operation principle of HPMU-TFLM are introduced. The flux-concentrating teeth and multi-unit concentrated winding are designed to improve PM utilization and reduce magnetic flux leakage. Then, the electromagnetic performances of HPMU-TFLM are investigated by the 3-D equivalent magnetic circuit model (EMCM) and the finite element analysis (FEA) method. Finally, its key performances of thrust density, power factor, and efficiency are compared with other typical transverse-flux linear machines (TFLMs). The superiority and feasibility of the proposed machine are verified.