Impact of thyristor controlled series capacitor on bulk power system reliability

A thyristor controlled series capacitor (TCSC) is expected to provide power systems with a number of benefits. This paper investigates its effects on bulk power system reliability. The reliability model of a transmission line with a TCSC is built and simplified via the state space approach. Optimal power flow (OPF) including the influence of TCSC is then introduced to decide the load curtailment. To examine the impact of TCSC, system reliability is evaluated in various operation environments, such as different TCSC placement locations and different line thermal limits. Finally, reliability is calculated assuming the TCSC is always working and the results are compared with those obtained using the model in which the failure of TCSC is considered. The insignificant difference indicates that the ideal TCSC model can be used for power system reliability analysis if the TCSC is highly reliable.