ESTIMATION OF RELIABILITY PARAMETERS FOR POWER TRANSFORMERS

Power transformers play an important role in the efficient delivery of power to consumers. Their failure leads to significantly higher losses and maintenance costs. Therefore, it is essential to have an optimal maintenance strategy in place for the transformers. However, to design an effective maintenance strategy, real failure data of the transformers need to be collected and studied to identify the failure patterns. To facilitate the analysis presented in this paper, five years of real failure data of a transformer system is collected from a power distribution company. The best-fit distribution for the failure times data of the system is found using AIC, BIC, and LKV values. Useful reliability parameters of the system are evaluated using the Maximum Likelihood Estimation and Rank Regression Method. Life data analysis is performed to estimate the reliable life, mean time to failure, and remaining lifetime of the entire system and its subsystems.