The Research On Reactive Power And Voltage Control Partitioning Method For Power Grid Containing Wind Power

The voltage stability problem becomes increasingly prominent in the modern power system. At the same time, large-scale wind power integration has a negative influence on system voltage stability and control. Therefore, it is of great significance to study reactive power voltage control for power grid containing wind power.Firstly, considering the requirements of soft tertiary voltage control partitioning on line, sensitivity matrix that contains voltage/reactive power coupling information between wind farm nodes, power and load nodes in power system is constructed, thereby electric distance matrix is solved based on sensitivity matrix. And then taking the closest electrical coupling between region nodes as optimization objective, partition model that ensures the connectivity of sub-partitions and reactive power reserve constraints is established. Taking advantage of improved genetic algorithm combined with ascending hierarchical merging, this method realizes the solving of best partition scheme and the selection of region pilot nodes. Secondly, this paper proposes the processing methods of wind farms during reactive power and voltage control partitioning for power grid containing wind power. Short-term wind power forecasting technique is introduced and the prediction model in which wavelet transforms and BP neural networks are combined is established, and then the forecast results are taken as flow calculation parameters. By means of modifying Jacobian matrix, power flow that meets the asynchronous wind turbine generator constraints is calculated. And then full-nodes voltage/reactive power sensitivity matrix is calculated based on Jacobian matrix containing wind farm nodes. Finally, reactive power and voltage control partitioning method for the power grid considering wind power integration is formed.The proposed partition method takes the uncertainty of wind power into account, and realizes power nodes and load nodes dynamic partitioning synchronically. In addition, the optimal partition number without prior determined can be chosen by partition algorithm according to the fitness value. The proposed algorithm with small searching space and high computational efficiency ensures the connectivity of sub-partitions and overcomes the traditional methods defects, such as requirement of manual intervention and low computational efficiency.The simulation of the IEEE39-bus system using Matlab programming and the electrical coupling verification of the partition results show that the proposed method is rationality and effectiveness.