摘要：为了研究无刷双馈电机偏心情况下的气隙磁场特性及其偏心故障检测方法，首先用解析法计算无刷双馈电机在未发生偏心故障和发生偏心故障两种情况下的气隙磁场分布，分析了电机在不同偏心状态下的磁场特性，并与正常电机相比较，然后确定用于检测偏心故障的气隙磁场特征信号，采用了用磁场谐波特征信号检测偏心故障的方法。最后，通过有限元仿真验证了理论分析的正确性，并对故障信号的幅值与偏心度的关系作了研究，为无刷双馈电机气隙偏心的精确检测奠定了基础。
关键词：无刷双馈电机；气隙偏心；磁场分析；特征信号；有限元仿真

Abstract: In order to study the characteristics of air gap magnetic field of the brushless doubly fed machine under eccentric condition and its eccentric fault detection method , firstly, with the analytical method, the air gap magnetic field distribution was calculated in the two cases that brushless doubly fed machine was in the absence of eccentric fault and the occurrence of eccentric fault,the magnetic properties of the motor under different eccentric conditions were analyzed,and compared it with the nomal motor,and then determined the air gap magnetic characteristic signal which was used for fault detection,based on the above, the method of detecting eccentric fault by using the harmonic characteristic signal of magnetic field was adopted. Finally, the correctness of the theoretical analysis was verified by the finite element simulation, and the relationship between the amplitude and the eccentricity of the fault signal was studied, which laid a foundation for the accurate detection of the air gap eccentricity of the brushless doubly fed machine.
Key words: BDFM；air gap eccentricity；magnetic field analysis；characteristic signal；finite element simulation