Research On Reactive Power Optimization Of Distribution Network With Reactive Power Participation Of Distributed Generatio

Energy is an essential resource for the development of a country.With the development of each country,the problem of energy shortage has gradually become a difficult problem for each country,and the greenhouse effect caused by the consumption of fossil fuel energy has become one of the main problems to be solved in the world.As one of the world’s largest population countries,China’s energy crisis is more urgent.The uneven distribution of energy and dependence on fossil fuel have been the main problems for China’s long-term development.With the proposal of "carbon neutral,carbon peak",new energy has gradually developed,and the development of distributed energy is more rapid.With the development of distributed power generation,when it is connected to the power grid system,it changes the power flow structure of the distribution network,making the original one-way power flow change into multi-directional power flow.Because of the randomness and uncertainty of distributed power generation due to the weather change,it has caused the phenomenon of voltage out-of-limit and voltage fluctuation of the distribution network,and even the phenomenon of improving the network loss of the distribution network and reducing the voltage quality,Reactive power optimization can solve voltage problems and reduce network losses.This article first introduces the background of the development of distributed power generation,and explains the problems brought by the connection of distributed power generation to the distribution network and the significance of studying reactive power optimization.Then,it explores the research status and development trends at home and abroad from three aspects: objective function,model solving algorithm,and multiple time scales,and briefly explains the research content of this article.Then the basic principles of photovoltaic power generation and wind power generation in distributed power generation were introduced,and the changes in voltage and system losses after they were connected to the distribution network were analyzed.Distributed energy,especially photovoltaic and wind power generation,will have some adverse effects on the economic operation of the grid after they are connected to the grid.Based on the economy and security of the distribution network,this paper proposes a comprehensive optimization model of the distribution network that takes into account the reactive power output of distributed power sources,considering the participation of wind turbines and photovoltaic in reactive power optimization.According to the structure of wind turbine and photovoltaic unit,the upper and lower limits of reactive power output are obtained.In order to overcome the situation that particle swarm optimization is easy to fall into local optimum,an improved particle swarm optimization algorithm is adopted.The IEEE33 system with photovoltaic and wind power has verified the impact of reactive power output of distributed generation on distribution network.The proposed model can further reduce losses,improve voltage quality,and realize the joint optimization of DG and static var compensator.Then the comprehensive reactive power optimization of distribution network under multiple time scales is proposed to further optimize the voltage quality and economic operation of the distribution network.In this paper,discrete compensation equipment and continuous compensation equipment are fully used to solve the voltage problem,and the final equipment control decision is given through the cooperation and optimization of the two time scales before and within the day.In the previous link,the method of load zoning is proposed,which can solve the problem of control times limit of discrete control equipment.Finally,a numerical simulation experiment is carried out in IEEE33 system to verify the effectiveness and superiority of the proposed method.