车用发卡式绕组永磁同步电机的设计与优化

Design and optimization of hairpin winding permanent magnet synchronous motors for vehicle

针对电动汽车对电机高效率和高功率密度的要求,结合发卡式绕组和内置式V型磁极结构的优势,设计了一台发卡式绕组永磁同步电机。根据电机的特点和设计指标,确定了电机的定子槽型和转子磁极结构,利用有限元方法(FEM)建立电机的二维仿真模型,验证了初步设计的合理性。针对电机齿槽转矩和转矩脉动较大的问题,首先,分析了不同转子分段斜极方式和分段数对电机齿槽转矩和输出转矩的影响,其次,利用田口算法对转子外侧辅助槽进行设计,完成了对电机转子结构的优化。对比转子结构优化前后齿槽转矩、转矩脉动、空载反电势以及气隙磁密的变化,证明了转子优化设计的有效性。最后,对优化后电机的磁场、外特性曲线、效率Map以及转子机械强度进行分析,结果表明,电机的输出性能和结构强度满足设计要求。

Aiming at the requirements of high efficiency and high power density of electric vehicle motor,a hairpin winding permanent magnet synchronous motor is designed by combining the advantages of hairpin winding and interior V-pole structure.According to the characteristic and design indicator of the motor,the stator groove type and the magnetic pole structure of the rotor were confirmed.The 2D simulation model of the motor was established based on the finite element method(FEM).The rationality of the preliminary design was verified.Aiming at the problem of large cogging torque and torque ripple,the influence of different step-skewed pole modes on cogging torque and output torque of the motor were analyzed.Second,the taguchi method was used to design the auxiliary slot outside the rotor.The optimization of the motor rotor structure was completed.Compared with the changes of cogging torque,torque ripple,no-load back potential and air gap flux density before and after rotor optimization,the effectiveness of the rotor optimization design were proved.Finally,the magnetic field,external characteristic curve,efficiency map and rotor mechanical strength of the optimized motor were analyzed.The results show that the output performance and structural strength of the optimized motor meet the design requirements.