Analysis of a Fall-Back Transverse-Flux Permanent-Magnet Generator

The conventional transverse-flux permanent-magnet generator (TFPMG), preferred for wind power applications, has a few limitations, e.g., the flux distribution in a U-shaped stator core is uneven, and its inactive permanent magnet (PM) poles lead to high magnetic flux leakage. In this paper, a new fall-back transverse-flux permanent-magnet generator (FB-TFPMG), suitable for direct-drive applications, is proposed to reduce the magnetic flux leakage between the stator cores and the PMs. In the proposed configuration, half the number of PMs (i.e., only active PMs) are employed with the elliptical-shaped stator core and toroidal-shaped coil. This leads to immediate benefit of lower mass and better flux utilization. The performance of the new topology is analyzed, under no-load and loaded conditions, using a 3-D finite-element tool, and the results are presented in comparison with the conventional TFPMG. The results show improved outcome of the proposed topology in comparison to the conventional TFPMG.