A Method for Assessing Margin and Sensitivity of Electricity Networks With Respect to Repair System Resources

Modern society is becoming increasingly dependent on a continuous supply of electricity. In order to maintain the safety and security of society and its citizens, it is therefore necessary that electricity networks are resilient toward disruptions whether caused by natural disasters, sinister attacks, or other. Margin and sensitivity are two crucial aspects of the resilience concept which have so far been subject to little research. Here a simulation-based method is presented that enables quantitative assessment of margin and sensitivity of electricity networks with respect to repair system resources. A simulation model is used that explicitly takes into account the electricity network as well as the repair teams and materiel necessary for repairing network components. The method is demonstrated for a municipal power distribution system in Sweden which is subjected to disturbances with a severity up to 12 independent failures (N-12). An overall conclusion from the case study is that the suggested method provides an overview of the margin and sensitivity of the electricity distribution system, with respect to repair system resources. This information can form the basis for decisions concerning what amount of resources is appropriate.