An energy approach to analysis of interarea oscillations in power systems

In this paper, an energy approach to analysis of interarea oscillations (IAO) in power systems has been developed. IAO is characterized as oscillatory behavior, following a disturbance, of the rotor motion for two or more generator groups such that there is a periodic interchange of energy between them. By comparing the phase of the coefficient of the dominant energy mode in the kinetic energy for each generator, we identify the groups for which there are periodic interchanges of energy. The location of these groups in the system provides insight regarding transmission lines over which the energy interchange is taking place. Numerical results are obtained using a test system similar in structure and characteristics to that of the WSCC system in North America. Time domain simulation indicates installation of thyristor controlled series capacitors in key transmission lines identified using the results of the energy analysis provides an effective control for damping IAO.