Abstract: With the advancement and implementation of China's “dual carbon goals”, the development of the electric vehicle (EV) industry has been rapidly progressing. Permanent magnet synchronous motor (PMSM) is widely used in the EV sector due to its high operational performance, high power density, and compact size. However, in automotive applications, factors such as limited installation space, poor heat dissipation conditions, complex operating conditions, and high-speed motor operation may lead to localized damage of the permanent magnets, resulting in partial demagnetization and degraded motor control performance. Therefore, researching, analyzing, and detecting localized demagnetization faults of permanent magnets is of significant importance. This paper takes a 10-pole PMSM as an example, replacing the magnet blocks to simulate localized demagnetization fault. Subsequently, a mathematical model of partial demagnetization is established, and theoretical analysis is conducted using Fourier transform to obtain fault characteristics during localized demagnetization. Finally, trial is conducted on a hardware-in-the-loop simulation platform to detect localized demagnetization faults, verifying the effectiveness and accuracy of the improved FFT method.

Key words: EV, PMSM, Partial Demagnetization, FFT

摘要： 随着我国“双碳”策略的推进落实,电动汽车产业发展日益迅速,永磁同步电机PMSM(Permanent Magnet Synchronous Motor,PMSM)由于高运行性能、高功率密度、体积小在电动汽车领域应用广泛。然而,在车用领域,安装空间有限、散热条件较差、运行工况复杂、电机高速运行,这些因素可能导致永磁体局部损坏,引起局部退磁,造成电机控制性能下降。因此,对永磁体局部退磁故障进行研究、分析、检测具有重要的意义。本文以一台10极PMSM为例,对电机进行磁钢块更换以模拟永磁体局部退磁故障。之后,建立局部退磁的数学模型,并使用傅里叶变换进行理论分析,得到永磁体局部退磁时的故障特征。最后,经硬件在环仿真实验平台上进行测试,检测局部退磁故障,验证了改进快速傅立叶变换FFT(Fast Fourier Transform,FFT)方法的有效性和准确性。

关键词: 电动汽车, 永磁同步电机, 局部退磁, FFT