The Research Of Coordinated Control Based On Agent Applying To High Voltage AC/DC System

During the process of carrying on the developing strategies " the west power transmitted to the east area" and the linked grid of the whole country presently , DC transmission , which can transmit huge power along a long distance and is easy to link with grid , is included in the project. With the complication and the fast development of modernized control techniques, many controllers are constantly used in AC/DC system, and these distributed controllers commonly function by receiving the local information (such as current, voltage and frequency) . In simple power system like single generator system, they work well, however, in complicated system, they can't behave well. Under some serious conditions, they don't even finish the local control tasks and at last influence the stability of whole system. Therefore, the coordination problem of controllers in AC/DC system has already been an important topic about power system stability.Up to now, according to the correlative references and research results, the controllers coordination problem is resolved by linear or non-linear optimized control theories. The power system is typical of nonlinear and timely-changed system. Based on the reason that the operation mode is constantly changed and many non-modeling part, the theory of linear optimized control can't do any favor to it . Although the non-linear theory can resolve the non-linear problem, it can not deal with the non-modeling part . Thus, other ideas must be introduced to resolve theproblems. In this article, the artificial intelligence and modernized control theories are combined to resolve the problems. By use of the prominent characteristics of Agent, a new thought is put forth to resolve the problem of coordination control in power system.In chapter 1, the development of AC/DC system and the coordinated control methods home and abroad are presented. At the same time, some problems existing are discussed.In chapter 2, by introducing the basic structure , the elements, control theory and control mode of HVDC, its main characteristics are presented. At the same time, the mathematical model of AC/DC system is presented.In chapter 3, the characteristics and basic structure are first introduced, and then, the MAS structure of coordinated control in power system is constructed. At last, the coordination mechanism of MAS is discussed.In chapter 4, the coordination mechanism of three generators AC/DC system is discussed, including the construction of MAS structure of three generators AC/DC system and the coordination project of every Agent. Every Agent is programmed by JDK2.0. Combined with the power system simulation software NETOMAC, the simulation results identify its effect.In chapter 5, to the low frequency power oscillation problem of south grid, the MAS structure of generators control and DC control is constructed, the coordination mechanism between generators control and DC control in South grid is discussed. The simulation result has identified that the method controls the low frequency power oscillation and improves the stability of AC/DC system.