Power System Application Tool for On-Line Security Investigations

In this paper a power system application tool is presented for on-line screening and ranking of power system states. The classification of contingencies is made on the basis of dynamic security criteria including threshold levels of important system parameters and limits of system stability. A brief technical insight in the components of the application is given. Based on a snapshot from EMS/SCADA the actual system state can be analyzed with respect to the contingencies and what-if scenarios, and with respect to the stead-state and dynamic limits. With the help of a modern computer system this can be done very fast and with great accuracy. Moreover, the same investigations can also be conducted for future real and hypothetical states considering a very short-term (e.g. 30 min) wind forecast and load fluctuations. An example is included, that shows possible control room integration and on-line use of the system. The paper also addresses the practical value of the tool. The major features are highlighted through a report on first experiences that a European transmission system operator has made while using the tool during the prototype testing period.