Multifactorial Frameworks Modelling Linkages of Power Transformer Failure Modes

Power Transformers are among the most critical assets in a power system, with significant costs as well as long lead times for acquisition. Their failure compromises the power system security. Total protection from electrical, mechanical, chemical and environmental stresses are near impossible leaving them vulnerable to failure via multiple mechanisms. Many researchers have analyzed the various failure mechanisms and have attempted to link specific mechanisms to the physical manifestations responsible for the ultimate failure of the transformer. This paper provides a library of failure frameworks in the various components of the transformer (core, windings, bushings, tank, cooling fins) and their link to the transformer dielectric materials (oil and cellulose). This paper will integrate published studies into a series of structured frameworks. Each framework provides a platform on which to develop improved models of plant reliability, identifying direct linkages between the transformer failure mechanisms and failure modes. With the identification of these linkages, reliability engineers can better understand how transformers fail and the measurands present at the time of failure, thus allowing for implementation of predictive/preventive maintenance regimes that shall be effective in identifying potential failure modes.