Power Transformer Fault Diagnosis Based on Controlled Switching Vibration Analysis

A method of power transformer mechanical structure fault diagnosis based on controlled switching process vibration measurement is presented in this paper. Compared with steady state loading condition, vibration generated in the controlled switching process contains abundant information of transformer mechanical structure. The wavelet packet decomposition is used to detect the signal envelop of such vibration response signal. Through theoretical analysis, the dynamic characteristic of transformer structure is approximately viewed as a second-order system and by estimating the time constant values, the potential defects of the transformer mechanical structure can be detected.