VP10-04 Analysis and Verification of Motor Performance Based on Local Carburizing of Rotor
Creators: Yulin Li
Chao Sun
Changhao Yan
Weizhou Li
Lubin Zeng
and Ruilin Pei
Publisher: name: IEEE
Year: 2025

In the future, high speed and high efficiency are the development trends of electric vehicle drive motors [1]-[2]. At present, most of the core materials of the drive motor are non-grain-oriented (NGO) silicon steel, and its performance determines the characteristics of the drive motor. For meeting the high speed, high efficiency and reliability of the drive motor, NGO silicon steel must not only have excellent magnetic properties, but also have higher yield strength, so that the rotor can resist the huge centrifugal force generated during high-speed rotation [3]. Carburizing is a heat treatment process to increase the carbon content of the alloy surface and improve its strength. Carburizing process is generally applied to the preparation process of alloy or grain-oriented silicon steel, and there are few cases in literature describing the application of NGO silicon steel to motors after carburizing. In this study, NGO silicon steel was carburized and innovatively used in the rotor, and its magnetic and mechanical properties were further investigated. Based on vacuum carburizing furnace and Thurckon PAC for stop-off paints, the local carburizing of flux barrier and rib in rotor was completed. As a result, the strength of the rotor is increased, thereby increasing the maximum speed of the motor. The purpose of this research is to improve the maximum speed and torque of motor based on carburized silicon steel, which is finally applied to the vehicle drive motor. The magnetic permeability of the silicon steel decreases after carburizing, which can reduce the magnetic leakage of the motor. In addition, the flux barrier can achieve a higher yield strength after carburizing, which can make the motor reach a higher speed. The finite element simulation analysis shows that the rotor can withstand greater stress after local carburizing. The maximum speed has been increased by 2,000 r/min or even more. On the other hand, the maximum efficiency of the motor is reduced from 97.3% to 96.85%, which is acceptable. From the test results of the motor, this research has been verified to be reasonable and it has the engineering feasibility.References: [1] Aldo Boglietti, Chris Gerada, Andrea Cavagnino. High-speed electrical machines and drives [J]. IEEE Transactions on Industrial Electronics, 2014, vol.61(6):2943-2945. [2] Gerada D, Mebarki A, Brown N L, et al. High-speed electrical machines: Technologies, trends, and developments[J]. IEEE Transactions on Industrial Electronics, 2014, 61(6): 2946-2959. [3] Tenconi A, Vaschetto S, Vigliani A. Electrical machines for high-speed applications: Design considerations and tradeoffs[J]. IEEE Transactions on Industrial Electronics, 2014, 61(6): 3022-3029.
In the future, high speed and high efficiency are the development trends of electric vehicle drive motors [1]-[2]. At present, most of the core materials of the drive motor are non-grain-oriented (NGO) silicon steel, and its performance determines the characteristics of the drive motor. For meeting the high speed, high efficiency and reliability of the drive motor, NGO silicon steel must not only have excellent magnetic properties, but also have higher yield strength, so that the rotor can resist the huge centrifugal force generated during high-speed rotation [3]. Carburizing is a heat treatment process to increase the carbon content of the alloy surface and improve its strength. Carburizing process is generally applied to the preparation process of alloy or grain-oriented silicon steel, and there are few cases in literature describing the application of NGO silicon steel to motors after carburizing. In this study, NGO silicon steel was carburized and innovatively used in the rotor, and its magnetic and mechanical properties were further investigated. Based on vacuum carburizing furnace and Thurckon PAC for stop-off paints, the local carburizing of flux barrier and rib in rotor was completed. As a result, the strength of the rotor is increased, thereby increasing the maximum speed of the motor. The purpose of this research is to improve the maximum speed and torque of motor based on carburized silicon steel, which is finally applied to the vehicle drive motor. The magnetic permeability of the silicon steel decreases after carburizing, which can reduce the magnetic leakage of the motor. In addition, the flux barrier can achieve a higher yield strength after carburizing, which can make the motor reach a higher speed. The finite element simulation analysis shows that the rotor can withstand greater stress after local carburizing. The maximum speed has been increased by 2,000 r/min or even more. On the other hand, the maximum efficiency of the motor is reduced from 97.3% to 96.85%, which is acceptable. From the test results of the motor, this research has been verified to be reasonable and it has the engineering feasibility.References: [1] Aldo Boglietti, Chris Gerada, Andrea Cavagnino. High-speed electrical machines and drives [J]. IEEE Transactions on Industrial Electronics, 2014, vol.61(6):2943-2945. [2] Gerada D, Mebarki A, Brown N L, et al. High-speed electrical machines: Technologies, trends, and developments[J]. IEEE Transactions on Industrial Electronics, 2014, 61(6): 2946-2959. [3] Tenconi A, Vaschetto S, Vigliani A. Electrical machines for high-speed applications: Design considerations and tradeoffs[J]. IEEE Transactions on Industrial Electronics, 2014, 61(6): 3022-3029.