Comparison of Mechanically and Electrically Excited Vibration Frequency Responses of a Small Distribution Transformer

A clear understanding of the vibration characteristics of power transformers is necessary to detect electrical and mechanical faults in a transformer using vibration-based monitoring strategies. This paper focuses on the measurement and analysis of the vibration frequency-response functions (FRF) of a 10-kVA distribution transformer due to mechanical and electrical excitations. The modal characteristics of the transformer are extracted from the FRFs, and can be used for reference models for future transformer fault detection. The effect of the magnetizing hysteresis in the transformer core on the measured FRF is also examined.