A Hybrid Analysis Approach for Transient Stability Assessment in Power Systems

The computational complexity involved in time-domain simulations, commonly used for analyzing transient stability in power systems, usually limits system studies to a few scenarios during the planning process. Complete analysis, however, requires investigation of all possible contingencies and consideration of the continuous changes in the operating point, which necessitates fast analysis techniques during network operation. The present paper introduces a hybrid analysis approach combining a direct-method and time-domain simulations for the fast analysis of power system transients. The combined analysis relies on a Lyapunov-based direct approach using the Potential Energy Boundary Surface (PEBS) method for a fast selection of critical contingencies in the first stage. In the second stage, the critical contingencies are further investigated by time-domain simulations. Simulation results are presented using a real network of the Baden-Wurttemberg state (Germany) in order to illustrate the simulation process of the implemented approach.