| Under the driven of energy-saving and emission-reduction, renewable energy generation was merged into the various voltage levels of power grid in the form of centralization, decentralization or micro-grids. The sources form (such as wind, photovoltaic, storage, thermal and hydropower) was becoming diversified day by day. Because the distributed generation exists in various voltage levels of power grid, the power sources of the power grid is becoming more and more unbalanced whether in area or capacity.The renewable energy generation has the characteristics of intermittent and fluctuation, so the capacity and the availability factor of the renewable energy generation located in every voltage levels at every moment are different Under the driven of being utilized maximized, the direction of power flow is becoming unclear, and the boundary of traditional transmission and distribution is brokea The dispatch and control methods which clear in logical by the way of generation, transmission, distribution and consumption are becoming invalid.In order to take full advantage of the renewable energy generation, because of their variability and uncertainty, the power grid must coordinate the wind, photovoltaic, storage, thermal and hydropower. The information of the power grid is decentralized and it is unavailable for the traditional centralized dispatch and control methods, so the traditional centralized dispatch and control must develop towards decentralized.Facing the situation of the power source unbalanced distributed, the power flow direction unclear, information centralized towards decentralized, so the centralized dispatch and control method must be changed, if not the renewable energy generation will not be used maximized.Therefore, in order to solve this problem, the various voltage levels of power grid in power grid (include traditional generation, transmission, distribution and consumption) must be dispatched and controlled integratedly. Base on this line, under the condition of power grid operation states panorama observation, the theory of the dispatch and control of power grid is studied. It is composed of seven parts. Firstly, the base of power grid operation states panorama observation is introduced. Secondly, the topology analysis method of the power grid is presented. Thirdly, the concept of aggregated grid and its formation are presented. Fourthly, the method of forming the observable point observable function is raised. Fifthly, the law mining method of observable point observable function is provided. Sixthly the dispatch and control function of aggregated grid and its applications are given. Seventhly, the coordinate dispatch and control function between multiple aggregated grids and its application are put forward. The seven parts correlate with each other, going forward one by one, and forma full theoretical framework. The main works and innovative achievements of this thesis are as follows:(l)The base of power grid operation states panorama observation and the way of its information management are introduced. First of all, the concept of power grid operation states panorama observation is provided. On the base of current study, the information management method of power grid operation states panorama observation is described and it is the base of later studies.(2)The topology analysis method of power grid is proposed. Based on summarizing the relative outcome, under the background of renewable sources such as wind, photovoltaic permeating into the every voltage levels in the form of centralized, decentralized and micro-gird, the basis of realizing the dispatch and control of power grid is getting the topology of power gird. Because the information of the power grid is managed by the way of decentralized, the current topology analysis methods can not be applied. So the station topology analysis method which using the way of independent and parallel is get, and the coordinated method between stations is presented to realize the topology analysis of the power grid.(3) The concept of aggregated grid and its formation method are presented. Aiming at the difficulties of the power grid scope large and information decentralized, under the wide-area environment, the concepts of observable point, observable point observable function, aggregated grid, aggregated grid dispatch and control function are provided. And the power grid coordination dispatch and control ideas and frame based on aggregated grid and between its dispatch and control are provided. The key problem of realizing them is forming the topology of the aggregated grids which in the power grid topology. So, on the basis of forming the power grid topofogy, the method of forming the topology of aggregated grids is proposed by the way of decentralized and coord ination.(4) The forming method of the observable point observable function is raised. On the basis of forming the topology of aggregated grids, using the single aggregated grid as the study target, under the guidance of observable point, the concept of observable point observable function and its two connotations are presented. Under the concept, the characteristics of two kinds of observable point observable function are held out. Based on applying Thevenin equivalent method to the station and getting its parameters, the relations between active controls, passivenesses in the station and the parameters of Thevenin equivalent are provided, and the two kinds of observable point observable functions are forming. Through this study, it is of great significance for reducing aggregated grid analysis, dispatch and control.(5)The law mining method of observable point observable function is provided. On the base of forming observable point observable function, using the single aggregated grid as the study target, taking the observable point voltage level as example, the law of the voltage aggregations and their controls periodical changes is presented using the Q iactor statistics. Through this study, it can be got the law of aggregated grids running and realized the dispatch and control.(6)The forming method of aggregated grid dispatch and control function and its application are given. There are some observable point observable functions in the aggregated grid, every observable point observable function is corresponding to a station. Under the environment of wide-area measurement, every station in the aggregated grid can form and store the information of observable point observable function followed by system periodical running. The information includes prediction, decision and control (correction). When the station local load is forecasted, the local history information is studied based on the iterative learning controlling theroy and the controlling values can be gradually changed. So the observable point dispatch and control function can be get, and its combination can form the aggregated grid dispatch and control function. When the active power of transmission line in aggregated grid violation, the observable point dispatch and control function can be coordinated to eliminate the overloading. This research combines the observation and controlling and it is significant to realize the dispatch and control in the situation of the flow direction unclear and the information decentralized.(7)The coordinate dispatch and control function between multiple aggregated grids and its application are put forward. The liaison station is the coordination of multiple adjacent aggregated grids, and actually multiple adjacent aggregated grids linkage by the observable points in the liaison station. So, the coordinate equation of the observable points in the liaison station is proposed. Combining with the single aggregated grid dispatch and control function, the coordination dispatch and control function between aggregated grids is proposed. The blackboard model is selected to solve the function. Taking the real system as example, experimental results verify the effectiveness of the proposed method. Through this research, the resources complementation in power grid will be realized. |
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