TRANSIENT STABILITY ASSESSMENT FOR NETWORK TOPOLOGY CHANGES - APPLICATION OF ENERGY MARGIN ANALYTICAL SENSITIVITY

Recent developments in direct transient stability assessment using the Transient Energy Function (TEF) method have included the exit point t echnique to determine the controlling unstable equilibrium point (uep) . In this paper, analytical sensitivity of the energy margin is couple d with the exit point based TEF method to assess system stability when there is a change in system parameters: plant generation or network c onfiguration. The principal featurs of this paper include: . introduct ion of a very fast sensitivity techniques to account for network confi guration changes. . elimination of the assumption that the mode of dis turbance of the controlling uep does not change. . correlation of the sensitivity results with time simulation through swing curves. The tec hnique is tested on the 50-generator IEEE test system and the 161-gene rator Northern States Power (NSP) system.