Research On Power Grid Thermal Stability Security Analysis And Control Strategy Under Key-node Spaces

Due to the reverse distribution characteristics of China's load center and power center,a large amount of power needs to be transported over long distances through the power grid.At the same time,China's power grid will inevitably become a weak interconnected large power grid,the complexity of the grid operating environment and the increase of uncertainties will make it more demanding for thermal stability security analysis and control methods.Therefore,through further study of a practical case in southern China,this paper proposes a set of grid thermal stability security analysis and control strategy method under key-node space,and develops the model into visualization software for online system.Specifically,the main work of this paper includes the following three points:(1)The thermal stability security region and its visualization model in key-node space are proposed.Firstly,the key-node of transmission section is obtained by the decision algorithm.Then the thermal stability security region is derived in the key-node space.In order to apply the model to the actual engineering field,the security region visualization model expressed by the combined plane graph is derived.(2)An active security control strategy is proposed for online analysis of power grid based on multi-slack sensitivity.Firstly,the single-slack sensitivity matrix under the AC power flow model is obtained.Then the concept of multi-slack sensitivity is proposed,and the correction factor between the multi-slack and single-slack sensitivity matrix is derived by quasi-steady-state method.Finally,a set of active security control strategies for online analysis is proposed using multi-slack sensitivity.(3)Developed a set of thermal stability security analysis and visualization software for online system of power grid through C++ language.The software is a programmatic implementation of this paper' method.The method in this paper is applicable to the interconnected large power grid system and verified by the actual engineering case of a power grid.