基于连续细化傅里叶变换的双馈风力发电机电刷滑环磨损故障诊断

Fault Diagnosis of Brush Ring Wear in Doubly-Fed Induction Generator Based on Continuous Subdivision Fourier Transform

摘要: 在实际工程应用中，电刷滑环系统故障较为频繁。作为双馈风力发电机(DFIG)的重要组成部分，电刷滑环系统磨损故障将会影响发电机的稳定运行。针对这一问题，提出一种基于连续细化傅里叶变换的DFIG电刷滑环磨损故障诊断方法。首先分析了DFIG电刷滑环磨损故障机理。然后通过仿真得到不同故障情况下的电气量，选取定子线电压和定子平均瞬时功率信号，基于连续细化傅里叶变换进行故障特征量的提取，验证了诊断方法的可行性。最后对不同故障类型和故障严重程度下的故障特征量进行对比分析。

Abstract: In practical engineering applications, faults in the brush ring system are relatively frequent. As an important component of a doubly-fed induction generator (DFIG), the wear fault of the brush ring system will affect the stable operation of the generator. A DFIG brush ring wear fault diagnosis method based on continuous subdivision Fourier transform is proposed to address this issue. Firstly, the wear mechanism of the DFIG brush ring was analyzed. Then, the electrical quantities under different fault conditions were obtained through simulation. The stator line voltage and average instantaneous power signals were selected, and the fault feature quantities were extracted based on continuous subdivision Fourier transform, verifying the feasibility of the diagnostic method. Finally, the fault characteristic quantities under different fault types and fault severity were compared and analyzed.