Nonlinear Control Design of Series FACTS Devices for Damping Power System Oscillation

Problem statement: The disturbance in the complicated network of power system may cause in nonlinear response. Static Synchronous Series Compensator (SSSC) is a power electronic based device that has the capability of controlling the line current. This study applies the SSSC to decrease the over line current in power system during dynamic state. Approach: This study proposes the control strategy of a SSSC to enlarge the stability region of a simple power system. The control is determined very carefully to satisfy the Lyapunovʹs stability criterion and is found to be a non-linear function of system states. The proposed nonlinear control of SSSC for damping power system oscillation is investigated through the sample system. Results: The maximum generator rotor angle of the faulted system without a SSSC is continuously oscillation and the maximum value is much more than the system with a SSSC. Conclusion: SSSC based the proposed nonlinear control can damp power system oscillation.