The conceptual framework of resilience and its measurement approaches in electrical power systems

The resilience assessment of complex and large-scale systems such as electrical power systems has becoming an inseparable part in analysing the reliable performance of the systems in the presence of high-impact, low-probability (HILP) incidents, such as extreme natural disasters. Considering the application of the resilience in various domains, the different definitions can be found for assessment of resilience in one system and several approaches can be applied to measure it. The necessity of increasing the resilience of power system infrastructures in response to HILP disasters for supplying at least emergency loads when facing unexpected and catastrophic events has becoming more and more clear. Reliability evaluation of power systems provides the likely behaviour of a system in normal condition but fails to model the high order contingencies which have low probabilities of occurrence. However, withstanding, absorbing and rapidly recovering from HILP events still remains a significant challenge which can be analysed in resilience assessment. This paper presents a conceptual framework of resilience domains and its measurement approaches, especially a thorough conceptual framework of resilience as a subcategory of vulnerability in electrical power systems. The conceptual difference between resilience and other indices of power system assessment such as reliability, risk and security are also presented in this research.