Studies On Methods Of Network Partitioning For Reactive PowerVoltage Control Based On Complex Network Theory

With the continuous interconnection of power grids in various regions,the scale of the power grid has evolved from a small-scale local power grid to a large-scale interconnected power grid,which will become the direction of global power grid development,and the complexity of power grid operation and control has greatly increased.Through the existing research,it is found that the grid shows the basic characteristics of complex network,which is transformed into complex network,and then the complex network theory is used to study the grid partition.Based on the complex network theory,this thesis studies the reactive voltage division of power system,which divides the power grid into sub-regions decoupled from each other.The main research contents are as follows:Firstly,This thesis studies the background and significance of grid decoupling,classifies and summarizes the existing grid partitioning methods,deeply studies the existing domain decoupling model and decoupling methods,and obtains the shortcomings of existing partitioning methods.Improve the partition model and method accordingly.Secondly,A reactive voltage partitioning method based on comprehensive evaluation indicators is proposed.Through the four indexes of the degree centrality,the betweenness centrality in the complex network,and the unsynchronized diffusion time and the critical synchronous coupling strength in the complex network dynamics,the key evaluation indexes of the key nodes are constructed,and the key nodes are selected from the load nodes.The key node coordinate space is constructed,and then the load node in the improved Kohonen neural network partitioning system is used to complete the division of the power node,according to the regional voltage control sensitivity,complete the partition of the whole power grid,and finally check and adjust the sub-area to output the optimal partition result.Finally,A two-stage reactive voltage partitioning method based on modularity optimization is proposed.The first stage is to evaluate the indicators through the degree centrality and betweenness centrality in the complex network,select the central node,and cluster based on the central node,and the adjacent direction according to the maximum increase or maximum decrease of the modular increment.The load nodes are merged,the power nodes are merged according to the short-circuit impedance distance,and an initial partition is obtained.The second stage is to establish a partition model based on electrical distance,with the modularity as the objective function,and the regional decoupling of the power grid by the improved particle swarm optimization algorithm,output the optimal partition result.