Dynamic stability enhancement of a multi-area multi-terminal DC-AC system with self-tuning Static Var Compensator

The application of an adaptive pole shifting self tuning Static Var Compensator (SVC) to a multi area multi terminal HVDC system is described. The developed scheme employs generator speed deviation as a feedback signal through the proposed Proportional-Integral-Derivate (PID) controller to generate control input for the studied system. The self tuner for the static reactive power system control is based on the minimum variance control strategy. Parameter estimation has been done using recursive least square identification routine with a variable forgetting factor. A digital simulation of the system following a three phase fault is performed to demonstrate the robustness and effectiveness of the developed controller. Results presented in the paper show that this adaptive controller performs better than a conventional unit. It is easy to implement because only the locally available measurements are used. Studies also show that there is no conflict between the proposed SVC and other kinds of power system controllers on the system.