Cooperative Control Of Statcom Based On Differential Games

With the rapid development of power industry, the capacity of the power system keep increasing, and power grid structure is increasingly complex and large. It is in urgent need to study new type of power control device to enhance the controllability and flexibility of the transmission and distribution system. In recent years, the emergence of FACTS devices provides an effective way to the flexibility of for power transmission. Static reactive compensation device(SVC and STATCOM, etc.) has significant advantages in such aspects as the range of operation, controllability and response speed. They can effectively increase the transmission capacity of power system and improve the static, transient state stability, therefore, they get more and more widely attention. The research in FACTS device focuses on FACTS device modeling, analysis of FACTS devices for power system steady state and the improvement of stability, etc. And some researches show that there are interactions between multiple controllers in the FACTS devices, which undermining the power system stability. It is pointed out that the interaction between multiple controllers in UPFC, the interactions between AC and DC controller in STATCOM is analyzed. However, the research about the interactions of STATCOM is still little, in this paper, we focus on the effects of the interaction between the DC voltage controller and AC voltage controller on STATCOM. The main contents can be summarized as the following respects:1. The problem the modern power system are faced with and the development of STATCOM are briefly described; otherwise, we introduce the operating principle and research status of STATCOM.2. This paper introduces the research history of differential game theory and its mathematical model, and focus on the open loop differential game theory and feedback differential game theory.3. Taking single machine infinite system as the research object, we induce the equations of the electric power system with static synchronous compensator model, and the simulation verify the negative interactions between the DC voltage controller and the AC voltage controller of STATCOM.4. The cooperative control model using differential game in single machine infinite system with static synchronous compensator is deduced. The open-loop Nash equilibrium and feedback Nash equilibrium are solved, which verify the negative interactions between the DC voltage controller and the AC voltage controller of STATCOM.5. We design and simulate the optimal control model, the traditional PI control model, the DC voltage control model of STATCOM. Then we compare the differential game with other three control methods through simulating, and verify the effectiveness and superiority of the model based on differential game.