Mechanical Fault Identification Method for Ⅴ-type On-load Tap Changers Based on Vibration Signal Analysis
The on-load tap changer(OLTC)is a critical component in transformers,which undergoes frequent operations and is prone to mechanical faults,leading to serious safety incidents.The switching principles of the Ⅴ-type OLTC is analyzed,and three common mechanical defects are introduced on a specific Ⅴ-type OLTC.Multi-channel vibration sensors are employed to collect vibration signals during the switching processes.A vibration signal analysis-based method for mechanical fault identifica-tion in Ⅴ-type OLTCs is proposed.Firstly,the CCEMDAN algorithm is used to decompose the vibration signals.A feature ma-trix is constructed based on the correlation coefficient method,and singular value decomposition(SVD)is utilized for feature extraction.Secondly,optimal measurement points for vibration signals are selected through principal component analysis and K-means clustering.Finally,mechanical fault classification is achieved using the XGBoost ensemble learning algorithm.Experimen-tal results demonstrate that the vibration signals measured on the front side of the OLTC enclosure better reflect its internal mechanical state.The proposed method achieves an identification accuracy of 98%for the three types of mechanical faults,sur-passing ensemble learning algorithms such as random forests and GBDT.
on-load tap changermechanical faultvibration signalfeature extractionensemble learning