Improving the FMEA Method to Failure Risk Assessment of Transformers, A Case Study in Tehran Electric Power Distribution Transformers

Distribution transformers play a pivotal role in power networks, serving as critical assets whose failure can lead to substantial expenses for replacement or repair. This study employs an improved Failure Modes and Effects Analysis (FMEA) method, utilizing transformer failures within the Tehran Electric Power Distribution Company over a decade. The Risk Priority Number (RPN) criterion assesses the failure probability associated with various failure modes for quantization within the FMEA method. Risk prioritization is determined through the RPN formulation. This paper proposes new improvements in FMEA, including an expert-based weighting method applied to the weighted RPN's sub-parameters to enhance precision and calculate RPN values based on the age group of each transformer. Subsequently, strategic corrective actions are proposed and implemented to mitigate the risk of transformer failures in the upcoming year. The culmination of this case study results in improved prediction capabilities and more effective failure prevention strategies for the company's transformers, facilitating purposeful asset management.