Investigation of Integer/Fractional Slot Consequent Pole PM Machines with Different Rotor Structures

Abstract

This paper investigates several integer and fractional slot consequent-pole permanent magnet machines (CPM) with different rotor structures. Besides the conventional SPM rotor, the most commonly used rotor structures for conventional IPMs such as the I-shape (I–IPM) and V-shape (V-IPM) are employed for comparison. The electromagnetic performance such as back-EMF, on-load torque, PM eddy current losses and dynamic characteristics are compared using 2D finite element analysis. In addition, the 3D thermal models including end-windings and end plates are established to predict the temperature variations in different machines. Then the demagnetization withstand capabilities of different CPMs are analysed by taking into account the temperature influence on magnet working point. It is found that the CPMs with IPM rotors have much better demagnetization withstand capabilities compared with their SPM counterparts.