Study On Reactive Power And Voltage Optimization Of Distribution Network Based On Source Load Interaction

At present,with the transformation of China’s energy strategy,under the background of"double carbon",China’s renewable energy power generation and energy storage technology has developed rapidly.With the access of emerging power sources and loads such as wind turbines,photovoltaic generator sets,and electric vehicles,the distribution grid is more complex and more volatile,thus making the voltage management of the distribution grid more difficult.If only the traditional reactive voltage coordination and optimization means of the distribution grid are adopted,such as adjusting the transformer tap and the number of feeder capacitor groups,etc.,it will be impossible to effectively adjust the voltage distribution of the distribution grid.Therefore,it is necessary to enrich the reactive voltage regulation means of the distribution grid under the new energy environment.With the development of power electronics technology,the reactive power output of distributed power sources such as double-feed wind generator sets can be adjusted smoothly.In addition,energy storage technology can also adjust the voltage and network loss of the distribution grid through rapid energy switching.As the user side response in the new energy environment,the flexible load can also be considered as a control means for the reactive voltage coordination and optimization of the distribution grid in the new energy environment.Given the above problems,the paper establishes the stochastic models of traditional load,electric vehicle charging load,doubly-fed wind turbine,and photovoltaic power generation system output by analyzing the uncertain factors existing in the distribution network under the new energy environment.In addition to the traditional control method of adjusting the transformer tap and the number of parallel reactive power compensation capacitor banks,a new control method of adjusting the flexible load power,distributed energy storage charge-discharge power and distributed reactive power output is added.A multi-objective opportunity-constrained programming model of reactive voltage with the objective function of network loss and voltage deviation is established for the distribution network under a new energy environment.The multi-objective optimization method of the improved NSGA-II algorithm was used to solve the source-load interaction distribution network model,and the Pareto solution set was obtained.A typical optimization scheme was selected from the Pareto solution set,and compared with the optimization before,the correctness and effectiveness of the model and its solving algorithm were proved.The influence of distributed power supply and EV charging load on distribution network loss and voltage distribution is analyzed by simulation.Simulation results show that this method can effectively reduce node voltage deviation and network loss of the system.