A segmented magnet interior permanent magnet machine with wide constant power range for application in hybrid vehicles

In traction application of hybrid vehicles, a wide constant power speed range is a necessity for efficient utilization of the power source. Due to its higher efficiency and torque/size ratio, the interior permanent magnet (IPM) machine is gaining popularity in many automotive applications including traction. However, most of the commercially manufactured IPM machines have a limited constant power range. In this paper, a segmented magnet IPM machine has been analysed for its suitability in traction application. This type of machine can offer very wide constant power speed range. The performance of the proposed machine is compared with a prototype IPM machine built in the University of New South Wales (in 1997) and an IPM machine commonly available in market from Kollmorgen.