A framework for coordinated stability control in the future GB transmission system using HVDC and power flow controller devices

This study investigates the possibility of using new transmission technologies such as Thyristor Controlled Series Capacitor (TCSC) and embedded High Voltage DC (HVDC) links to increase power transfer capabilities by means of improving the transient stability as well as oscillation damping in a power system. Initially, this paper discusses the need for stability control systems to ensure co-ordinated and optimal dynamic performance of power flow controllers in large integrated power systems such as the GB transmission system, following that a hierarchical control strategy for coordinated control of the TCSC and HVDC links for all operational points is proposed. Finally, the main objective of the study is to develop and analyse an operational Stability Control System (SCS) by implementation of a robust and stabilising multivariable feedback control system to guarantee the system robustness and stability against the various operational conditions. Therefore, the stability control system will be able to provide co-ordinated control of TCSC and HVDC links in order to achieve best dynamic performance and make the stability limits a less binding factor than the thermal limit under all operating conditions.