Monitoring vulnerability in power systems Extraordinary events, analysis framework and development of indicators

This paper addresses the needs for monitoring vulnerability in power systems related to extraordinary events. An analysis framework is described to identify threats, vulnerabilities, unwanted events and consequences. Vulnerability is an internal characteristic of the system comprising susceptibility and coping capacity towards natural hazards, human or technical/operational threats. Together with the external aspects of vulnerability, threats and consequences for society, vulnerability gives insight into risk related to extraordinary events. Based on this framework indicators are developed for monitoring vulnerability. For this purpose it is necessary to identify critical assets, locations and operating states. These are factors with potentials for severe consequences. Examples of vulnerability indicators are given for two different cases. The first case considers the power supply consisting of two power lines to a small community, where the main threats are storm and loading degree of the lines. The second case deals with a region where the main threat is a strained power situation due to limited generation and import capacity to the area. KeywordsVulnerability; risk; indicators; extraordinary events