An application of energy function for calculation of critical fault clearing time

This paper presents a method for calculation of critical fault clearing time (t_cr) using the energy function method. The method for calculation is the potential energy boundary surface (PEBS) and the controlling of unstable equilibrium point (UEP). Power system stability deals with the power system´s response to disturbances. The conventional transient stability studies use time domain. So that finding critical clearing time for clearing machine under fault condition is slow by the trial and error finding method. The applied time domain for transient assessment is not practical using for realtime transient stability assessment. Using the energy function is the way to make transient stability assessment possible in real-time. With this method the main point is the real critical clearing time (t_cr) for desired instability.