PROJECT TITLE :

A Mechanical Flux Weakening Method for Switched Flux Permanent Magnet Machines

ABSTRACT:

Many switched flux permanent magnet (SFPM) machines with mechanically movable flux adjusting technique are proposed, analyzed, and compared for applications which demand high speed and efficiency. By using ferromagnetic pieces-–one per every stator pole or every various stator pole, which are named as flux adjusters (FAs) and located on the surface surface of the stator—the airgap flux density will be weakened and therefore the operation speed range and flux weakening capability will be improved. The influence of using all or various FAs on the open circuit results, electromagnetic performance, and torque–speed characteristics of the SFPM machine is investigated through three SFPM machines with different stator/rotor pole combinations, i.e., 12/10, twelve/thirteen, and twelve/14. Moreover, though using FAs in all stator poles can significantly improve the flux weakening capability, different FAs can also achieve remarkable improvement though higher torque ripple is observed. Additionally, it has been found that the twelve/13 combination is considered to be the foremost suitable candidate for different FAs technique. Besides two-D finite-element analysis (FEA) and analytical strategies, 3-D FEA results accounting for the end-result are presented. Furthermore, experiments are performed to validate the results.