Allocation and design of power system stabilizers for mitigating low-frequency oscillations in the eastern interconnected power system in Japan

Low-frequency oscillations have been observed on trunk transmission systems in Japan, and have been the subject for studies in fields of operation, control, and devices by the many power system utilities. Power system stabilizers (PSSs) are very effective controllers in enhancing the damping of low-frequency oscillations, since the controllers can increase damping torque for inter area modes by introducing additional signals into the excitation controllers already equipped with generators. In this paper, allocation of PSSs in an interconnected power system with inter area modes has been determined by an eigenvalue analysis, and PSSs for the allocated generators have been designed by a frequency response method. The designed PSSs have been verified in a Japanese power system standard model. This test system is created as a standard model based on the trunk transmission systems in the eastern area of Japan, and reflects characteristic features of the real power systems; therefore, realistic allocation and design for enhancement of the stability of low-frequency oscillations have been verified.