A design of transverse flux motor with permanent magnet shield

Abstract

Transverse flux motors (TFMs) have a structure in which the direction of the current corresponds with the motion direction of the rotor, and a ring-shaped stator winding. The advantages of TFMs are high force density per volume and high efficiency because the resistance loss of winding end-turns is absent and the magnetic circuit is separated from the electric circuit. The authors designed two kinds of TFM, which are a variable reluctance type and a permanent magnet-shield type. The TFM with the PM-shield has a permanent magnet on the teeth of stator to shield it from airgap leakage flux, thereby increasing the power density. By analyzing these motors using 2-D and 3-D FEM and experimental measurements, the authors show the effect of the PM-shield.