Special HVDC controls for TNB/EGAT HVDC interconnection system

The actual controls system of TNB/EGAT HVDC interconnection system is implemented in a high-speed graphically programmable digital control system. This paper describes the features and operations of the controllers by giving a brief description of the pole control functional environment that is employed in the TNB/EGAT HVDC interconnection system. This paper then explains the custom model development of the special controls for the power order setting functions such as power run-up and run-back control, dual frequency modulation, frequency limit and transient current order control of the actual HVDC system. The purpose of these controllers is to improve the power stability of the AC-DC system. The dynamic performance tests of the developed models give a good response in terms of power stability improvement.