A Study on the Selection of Inspection Interval for Power Transformers through RBI

Power transformers play a crucial role in power transmission and substation systems, and a systematic and efficient inspection strategy is essential for stable operation. However, existing TBI methods only perform inspections at regular intervals, failing to adequately reflect actual equipment conditions. This can lead to over-maintenance of low-risk equipment and insufficient management of high-risk equipment, resulting in inefficient investment costs. Therefore, this paper proposes a risk-based inspection interval calculation strategy to address these issues. In this study, FMEA of the transformer was performed, and based on this, PoF and CoF were calculated to derive risk. The inspection interval was selected based on the risk of the power transformer. To verify the validity of the proposed RBI, simulations were conducted. The results confirmed that it is an effective inspection strategy that addresses the issues of existing TBI and ensures cost-effectiveness and reliability.