Ecological Uniqueness for Understanding Line Importance in Power Grids

The identification of critical components in electric power grids is an important challenge power engineers face. Similarly, many ecologists face the challenge of identifying important species in food web networks. Drawing similarities between power grid networks and food web networks, this study utilizes proposed identification methods from ecology literature to identify critical components in electric power grids. These ecological methods used include measures of Sum of the Trophic Overlap (STO) and Weighted Trophic Overlap (WTO). We also study a method proposed from power engineering literature that uses the Normalized Line Outage Distribution Factor (NLODF) to compare the different methods. The intention of this study is to determine if bio-inspiration in criticality metrics provides a feasible tool to use in power grid analysis. The proposed engineering method utilizing NLODF is found to be more accurate in identifying critical lines in power grids when considering all lines in the grid. However, the ecological metric STO is found to be as good as NLODF when considering the top 10,20, or 30% of lines. STO was the most accurate metric in the largest grid analyzed, suggesting STO may be more accurate in larger grids. The comparable performance of the ecological and engineering methods suggests the ecological methods can be used to accurately identify critical components in electric power grids.