Distribution Transformer Failure: Causes and Solutions from the Field Data Analysis

During the past ten years, tremendous growth has been observed in load. The overloaded grid assets, such as distribution transformers, which are a fundamental part of the distribution system, serve in severe and poorly maintained conditions, which account for heavy losses and often result in failure. The failure rate of Distribution Transformers (DTR) is significantly high, especially in developing countries, which leads to loss of revenue and poor customer satisfaction. Therefore, it becomes a need of the hour to study various reasons for DTR failure to identify dominant causes and possible corrective measures to improve the situation. This paper aims to analyze the prevailing situations in the Indian distribution systems based on historical data, field visits, and available infrastructure. Based on the findings, possible reasons for DTR failures are identified, and recommendations are proposed for minimizing the failure rate of DTRs.