A novel excitation controller to damp subsynchronous oscillations

A novel supplementary subsynchronous damping controller (SSDC) is proposed for the generator excitation system which is capable of damping out subsynchronous oscillations in power systems with series compensated transmission lines. It is shown that the controller is able to stabilize all unstable modes for all compensation ratios. Eigenvalue analysis and transient simulations of detailed nonlinear system are considered to investigate the performance of the controller. Robustness of the controller has been analyzed by facing the system with disturbances leading to significant changes in generator operating point. The IEEE Second Benchmark Model is considered as the system under study. All the simulations are carried out in MATLAB/SIMULINK environment.