Risk-based security assessment considering corrective control of TCSC devices

This paper investigates the effect of Thyristor Controlled Series Capacitor (TCSC) on risk-based security assessment (RBSA) of power systems. Based on a power-injection model of TCSC, an optimal power flow corrective control method is integrated into the RBSA process to remove emergency overloads caused by N-l line outages. The objective of the optimization problem is to minimize the control amount of TCSC. An improved piecewise function is adopted to reflect the overload severity level of the contingencies. In addition, a sensitivity based approach is adopted to determine the optimal location of TCSC. Simulation results on the IEEE RTS-79 system show that the proposed TCSC power flow control model is able to deal with post-contingency emergency overloads and could effectively reduce the system operating risk.