Power Transformer Reliability
Power transformers are essential components of transmission systems and often the most valuable asset in a substation. Winding construction is based on the time-proven technology of copper conductor, wrapped in cellulose insulation, and fully impregnated with insulating oil. With a Mean Time Between Failure (MTBF) above 100 years, transformers are regarded as highly dependable equipment. However, the general transformer population is now aging. This by itself would increase the risk of failure but it is compounded by the trend to load transformers to higher levels to meet economic constraints of deregulated power systems environment.