Magnet Design and Motor Performances of a Double Layer Interior Permanent Magnet Synchronous Motor

Abstract

In this paper we would like to discuss the results of our investigation of the Interior Permanent Magnet Synchronous Motor (IPM), which has permanent magnets embeded in the rotor, and in particular we are concerned with the Double Layer IPM Synchronous Motor, which has two layers of magnets embeded in the rotor layered in the direction of the radius. For this investigation, we studied the arrangement of permanent magnets both through simulation and experiments with a prototype. The results concerning the form of the magnets clearly show the superiority of the reverse arc form, which can increase the surface area creating magnetic flux. We further determined that to maximize both the qaxis flux and the flux of the permanent magnets, the optimum size for the q-axis flux path between the magnets for the motor studied on this occasion is 2 mm. In addition, the results clearly show that notching the ends of magnets is effective in further utilizing the q-axis flux.