A Risk Assessment Based Method for Prioritizing Power Substation Apparatus Maintenances

Proper planning for apparatus maintenance is of great importance to a power utility for maintaining power grid reliability while optimizing the resources. In this paper, a risk assessment-based method is proposed to prioritize power substation apparatus for maintenance. Firstly, a probabilistic failure model is developed for both power transformers and switchgears with the historical failure data. Secondly, the service of each apparatus is substituted into the failure model to derive the failure probability. Finally, the total risk including the maintenance cost, load curtailment cost, and failure risk are calculated with the failure probability, which is then utilized to derive the maintenance priority. Case studies are performed using historical data of low-voltage power apparatus in Singapore power grid.