Identification of coherent generators using energy function

A new method of identifying coherent generators for multiple faults in a power system is presented. A tentative coherent group of generators is initially determined by evaluating the energy function at different approximate unstable equilibrium points of the system. The final coherent groups for individual faults are obtained by checking relative rotor angles in the faulted system. The method is fast and saves a great deal of computation time. The proposed method was tested on three power networks and the results obtained perfectly matched with those found from classical simulation studies.