Design and Analytical Modeling of a Novel Permanent Magnet Synchronous Coupling for Switch Machine

In this paper, a new permanent magnet synchronous coupling (PMSC) is proposed for switch machines. Using the principle of magnetic field superposition, the magnetic field model of this coupling is established for the first time. Based on the scalar magnetic potential and Maxwell stress tensor, the distribution of the air gap magnetic field is derived in the 2-D model, and the analytical expression of the transmission torque is obtained. The accuracy of the analytical model is verified by comparing the results from the 3-D finite element method (FEM). The results show that the magnetic field characteristics of the air-gap magnetic field obtained by the analytical model are in good agreement with those calculated by the 3-D FEM. The prototype is fabricated and bench experiments are done. The performance of the coupling and the accuracy of the analytical model are verified.