This thesis presents the dynamic stability improvement of a large-scale power system which consists of a conventional synchronous generator (SG)-based power plant integrated with a doubly-fed induction generator (DFIG)-based wind farm by using a static synchronous series compensator (SSSC). The complete dynamic mathematical equations of the studied system are established in dq-axis reference frame under three-phase balanced conditions. In addition to the power flow control function of the SSSC, a proportional-integral (PI) type oscillation damping controller (ODC) is designed for the SSSC to offer adequate damping for the studied system. The proposed ODC for the SSSC is designed using the pole assignment method based on modal control theory. Both steady-state analysis of the studied system under various operating conditions and time-domain simulations of the studied system subject to different disturbances are carried out. The steady-state analysis and time-domain simulation results show that the studied system without SSSC suffers from low-damped low-frequency oscillations due to the electromechanical mode of the SG. The damping of these oscillations, however, is slightly increased when the SSSC is implemented in series with transmission line for controlling the power flow. The results obtained also show that the designed ODC for the SSSC can significantly increase the damping and, hence, effectively improve the dynamic stability of the studied system under various disturbance conditions.

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