Heatwaves and Duration of Distribution System Faults: A Comparison of Different Indexes

The temperature increase challenges both humans and infrastructures. In particular, one of the most evident phenomena is the rising of the number of high temperature periods (i.e., heat waves), whose severity, measured in terms of duration, results being higher than in the past. Heat waves affect, among others, the underground urban distribution system, with a rising of the faults of its constitutive elements (i.e., cables, cable joints and terminals). Recognizing when heat waves happen becomes hence important, for introducing new strategies for the improvement of the distribution system resilience. For this reason, this paper compares the performance of two different heat wave indicators, and calculates a covariance matrix between them and the fault duration. The results show that the Excess Heat Factor presents better performance than the Index of Heatwave, both in terms of heatwave period identification and in terms of correlation.