An investigation of a segmented rotor interior permanent magnet (IPM) machine for field weakening

The interior permanent magnet (IPM) machine is considered to be the one of the most efficient electrical machine. The high efficiency along with good performance characteristic makes them suitable for drive with wide speed range. The conventional IPM machine has almost nil or very little field weakening range. Many attempts have been made to improve the range by modification of rotor configuration. In this paper, different types of rotor configuration of IPM machine that is suitable for flux weakening operation has been reviewed. A new rotor design of segmented magnet has been studied by finite element (FE) analysis. The result of FE model of segmented magnet rotor and a conventional rotor of IPM machine has been compared and discussed. In the new design an improved flux weakening aspect has been noticed. Since the new design does not need any special construction effort, it could be a better solution for IPM rotor configuration suitable for field weakening operation.