Development of 31kW Interior Permanent-Magnet Synchronous Motor for Electric Vehicles

• Main Authors: Tzu-Ting Hsu, 徐子庭
• Other Authors: Jung-Ho Cheng
• Format: Others
• Language: en_US
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/81908518781717505061

碩士 === 國立臺灣大學 === 機械工程學研究所 === 98 === The objective of this work is to design a high-performance traction motor for a battery electric vehicle “Green Jumper” engineered in National Taiwan University. An important challenge of traction motor design for electric vehicle is to meet the requirements of different types of electric vehicles and of easy-to-construct configuration that can contribute to the overall cost reduction for the electric vehicle. The interior permanent magnet (IPM) synchronous motor is the natural choice of such niche applications because of their higher efficiency, compact size and achieving constant-power operation over a wide speed range with limited magnet strength requirement. However, the cost of magnet material is high compared with the cost of the other materials used in electric motor, and design attributes that minimize the required amount of magnet material are important challenge for high-performance motor design. The placement of the embedded permanent magnet is developed for the optimized design of high-performance IPM motor. The IPM motor with segmented magnet is first investigated in terms of its field weakening capability. Furthermore, this thesis proposed a design with permanent magnets being embedded in the U-shape flux barrier compared to the V-shape flux barrier of TOYOTA Prius. The comparisons of the average torque and no-load back EMF are given. The results of the motor performance comparisons are based on comprehensive use of finite element analysis tools (JMAG-Studio). From the FEA results, it shows that the U-shape flux barrier proposed in this work has better torque capability than the V-shape flux barrier adopted in TOYOTA Prius; that is, for a given torque, the design with U-shape flux barrier can yield a smaller motor with less amount of magnet and contribute to the overall reduction of the material cost. A prototype motor was constructed on the basis of the final optimized design. The no-load back EMF and the torque performance were measured and compared with the predicted results for experimental verification. Finally, the measured performance analysis was found to closely match with the predicted results.