Mechanical fault diagnosis method for OLTC based on MPE and K-means++ algorithm

On-load tap-changer (OLTC) is easy to fail because of the frequency switching operation. The vibration signals produced by the operation process show obvious nonlinear characteristics, but most of the existing methods of extracting OLTC running feature are based on the linear theory, and there are some limitations. In order to realize the mechanical fault diagnosis of OLTC under the nonlinear vibration signal, a kind of OLTC mechanical fault diagnosis method based on the multiscale permutation entropy (MPE) nonlinear analysis method is proposed. Firstly, the vibration signals are collected in the different mechanical faults of the OLTC in the laboratory. Secondly, the Cao's method is used to determine the MPE parameters and the MPE characteristic of the mechanical failure state of the OLTC is extracted. Finally, the K-means++ algorithm is used to identify the mechanical state of the OLTC and compares it with the clustering effect of the traditional K-means algorithm. The results show that Mechanical fault diagnosis method for OLTC based on MPE and K-means++ algorithm can effectively extract the mechanical fault characteristics of OLTC, and can correctly identify the OLTC mechanical fault, and its diagnosis effect is better than the traditional K-means algorithm, and the stability is high.