Sensitivity Analysis of Weighting Factors for Conditional and Importance Criteria in Gas Insulated Substation Health and Importance Indices

The effective maintenance of Gas Insulated Switchgear (GIS) in high-voltage (HV) substations is essential for ensuring system reliability and minimizing unplanned downtime. The percentage Health and Importance Indices (%HI and %ImI) are key metrics used to assess the criticality of various factors influencing GIS performance, such as equipment age, maintenance history, insulation quality, environmental conditions, and operational performance. This research performs a sensitivity analysis on the weighting factors applied to the %HI and %ImI, examining how changes in these weightings affect the indices. Using a weighting and scoring technique, the analysis investigates the impact of varying each parameter’s weight on the overall %HI and %ImI, identifying the most sensitive factors that influence maintenance decisions. The actual data for both the conditional factors and importance criteria are applied in these calculations. Subsequently, the actual scores of six units GIS are computed using ten different weighting sets. The results demonstrate that the weighting values follow a linear approach, where higher weight values indicate a greater influence on the respective criterion. In addition, the sensitivity of the weighting factors significantly impacts the process of adjusting the range for %HI and %ImI, ultimately affecting GIS health and importance identification and informing maintenance planning.