Multiterminal HVDC system control using a distributed computing technique

HVDC schemes are poised for a more significant level of acceptance in the large power transmission grid because of the proven experience that has been accumulated over many years with two terminal systems. Recent trends indicate that more multiterminal HVDC systems are emerging as an option for expansion. Derivation of the control strategy for a multiterminal case, however, requires the handling of a significantly larger number of state variables. There is also the need to optimize system performance taking into account the total `control effort' to be used. All this implies a need for more demanding computational power which will increase out of proportion to the increase of terminal numbers in the online control of multiterminal systems. The essence of the work presented in this paper is to get around this problem by adopting a distributed computing approach. The various features used to establish this distributed computing environment and the employment of this technique to facilitate the system controller in generating and coordinating commands for the overall optimal control of the AC-DC system are illustrated in the paper