Static Stability Stabilization Of Large Power Grid Based On Wide Area Information

With the global energy internet strategy been proposed,the grid scale is expanded,intermittent new energy networking pace is accelerated,the safe and stable operation of grid is facing a serious threat.The traditional modeling and simulation method is restricted by the model parameters,and its timeliness can not meet the demand of grid safety control.The development of the wide-area measurement system provides an opportunity for the security and stability assessment online.It can achieve on-line prevention and control,real-time assessment,meetting the control requirements of the grid.Therefore,it is very important to grasp the static stability mechanism of the power grid,carry out the online static safety and stability evaluation research,and develop the grid safety security system in the wide area environment.Firstly,this paper discusses the static stability mechanism of power grid.The method of thevenin equivalent parameter identification is summarized by the system.The grid stability mechanism was analyzed which based on the node savannan equivalent and the tributary elasticity mapping.Both of two can be attributed to “Source-Grid-Load” energy flow balance problem in the wide area environment.The static and stable analysis mechanism of the grid in the wide area environment is described as follows.For the problem of existing method can't satisfy the calculation online.The grid generalized parallel structure is established.All power grid nodes and load nodes are equivalent respectively.Furthermore,the grid is simplified to “Source-Grid-Load” two-node system.The equivalent output power,load power and total current are calculated.The angle of voltage and current is obtained by that way.Referenced by elasticity mapping ideas,the equivalent system is mapped to two nodes elastic branch.An online quantitative evaluation method for power system static stability based on “Source-Grid-Load” clustering and elastic mapping is Proposed.The overall and district stability of the system is calculated on the IEEE 39-bus system.The results verify the feasibility of the proposed method.Compared with the potential energy integration method,this method is improves the calculation speed greatly.In view of the existing problems of quantitative evaluation of power grid,the modulus of power indicators is derived as equivalent meaning based on the static transmission capacity of the grid and the impedance mode boundary characteristics.Combined with generalized“Source-Grid-Load” equivalent model and power mode indicators in grid.The static stable situation rapid quantitative assessment in overall grid can be implemented.The simulation results of two-bus system and IEEE 39-bus system verify the effectiveness and practicality of the proposed method.The method avoided uncertainty aspects of thevenin equivalent parametersidentify.The static stability index of the grid is quantified to 0-1,which satisfies the real-time and quantization requirements.In order to realize the development of grid security defense system platform,the visualization technology of power grid at home and abroad is studied,and the Web visualization technology of power grid based on ECharts is put forward.After a detailed analysis of the functional framework in the grid security defense system,the visualization framework is built.Based on the WAMS information,a large data technology is used to calculate the static stability assessment algorithm which based on the generalized “Source-Grid-Load” equivalent grid.Security defense panoramic visualization system are developed,the panoramic key information of grid is valid and intuitive image displayed.The visualization system improved the defense and situational awareness capabilities of intelligent power grid,protected the security and stability operation.In summary,this paper is based on the actual measurement or simulation information of grid.The thevenin equivalent parameters identification method,power grid unified stability mechanism in wide-area environment,generalized “Source-Grid-Load” equivalent of large grid,static stability index of whole grid,grid security defense system visualization and other aspects is studied comprehensively.The corresponding model and method are proposed,and the simulation results achieved good results.