ABSTRACT
Transformers constitute the largest single component of the transmission and distribution equipment market. Several major transformer reliability surveys, carried out under the auspices of Conference on Large High Voltage Electric Systems and Institute of Electrical and Electronics Engineers in order to assemble objective data on the performance of transformers in service, provide useful information. Vibration signal analysis is being pursued as a likely means of achieving a dependable transformer winding mechanical integrity diagnostic tool. The statistically more substantial results are those concerning substation transformers with on-load tap changers. The Power Systems Reliability Subcommittee of the Institute of Electrical and Electronics Engineers Industry Applications Society has been conducting surveys of the reliability of electrical equipment, transformers included, in industrial and commercial power systems. Several approaches have been developed with the purpose of providing an accurate and complete diagnosis of power transformers.
