Research On Power Grid Disaster Prevention Strategy Of Geomagnetic Storm Based On PMU Data

With the gradual expansion of China's power grid scale and the continuous improvement of voltage level,the threat of geomagnetic induced current(GIC)to the safe operation of power grid is increasing.In particular,the wide application of multi split transmission lines with smaller DC resistance per unit length,single-phase transformer and autotransformer makes the GIC level of China's power grid and its harm to the power grid continue to increase.The safe and stable operation of China's large power grid is also facing severe challenges.Starting from the distribution characteristics of GIC in China's power grid,this paper puts forward the real-time monitoring method and risk assessment method of GIC based on PMU data.On this basis,it further studies the geomagnetic storm disaster prevention scheme based on sharing GIC goal of power grid.The research results will provide reference for power grid dispatching and operation management departments to realize real-time monitoring and risk assessment of GIC risk assessment and scheduling prevention provide systematic theoretical methods and decision support.The main research contents and results are as follows:1)This paper studies and analyzes the value and distribution of GIC in China's 500kv-1000 kV typical power grid,summarizes the distribution law and characteristics of GIC in China's UHV power grid,and quantifies the influence of power grid parameters including transmission line length,line direction,DC resistance and topological structure on GIC by introducing sensitivity coefficient index.2)This paper proposes a scheme to obtain real-time grid GIC using the actual PMU data,analyzes the correlation between North China Grid PMU data and GIC during the two magnetic storms on September 8,2017 and May 14,2019,and proposes a grid GIC identification method based on PMU data and Kalman filter principle,The GIC distribution of North China Power Grid during two magnetic storms verifies the feasibility and applicability of the method.3)Based on the application of PMU data,a grid GIC risk assessment system is established.It is analyzed and verified that the historical data characteristics of magnetic storm conform to Pearson-? distribution.The entropy VIKOR method is used to realize the grid GIC risk objective assessment considering multi-dimensional factors on the basis of considering the sensitivity of grid structure parameters and the characteristics of historical data,Combined with the operation parameters of North China power grid,the simulation results verify the effectiveness of the method.4)This paper studies and summarizes the typical methods of geomagnetic storm disaster control,and from the perspective of regulation and operation,puts forward a geomagnetic storm control scheme based on line interruption method and improved GIC of power grid,which is verified by the actual grid structure of East China power grid.The results show that the line interruption method can be used as an effective regulation and operation means for the prevention and control of geomagnetic storm disaster in power grid.The results of this paper will provide a reference for geomagnetic storm disaster prevention in the field of regulation and operation,which is greatly significant to evaluate the risk of magnetic storm disaster in power grid and develop reasonable defense strategies.