Power systems security analysis-new approaches used at EDF

As most countries in the world have difficulties in building new transmission lines, the amount of energy transmitted through the existing EHV networks increases with the consumption level. This tendency is strongly reinforced with deregulation of electric markets. Therefore power systems have to be exploited closer to their limits. As a result, system stability becomes harder to control, which raises significant reliability problems. Major incidents affecting the power supply to a large number of customers are rare but may occur. The deregulation of electric markets also creates new uncertainties on data needed for dynamic studies, and a new hypothesis has to be taken into account. In this context, it becomes more and more important for Electricite de France to be able to justify and to optimise the cost of the measures that have to be taken to insure the security of the power system. Electricite de France intends to develop its methods and tools used in the security assessment domain. This report presents new trends for security studies: the introduction of a statistical approach in our security studies, first step towards of a probabilistic approach. Our perspectives are to develop the use of these kind of dynamic studies with a statistical approach, to new application cases and to create a new general tool based on our statistical approach. We are also working on a probabilistic approach in order to integrate the weight of incidents, situations etc. to this kind of study.