Research On Location Capacity And Reactive Power Control Of Distributed Photovoltaic Power Connected To Distribution Network

With the continuous reduction of traditional energy reserves and the increasing global energy demand,distributed photovoltaic energy has become one of the hottest research areas of new energy because of its large reserves,environmental protection and pollution-free advantages.When the distributed photovoltaic power generation system is connected to the grid,the voltage and power deviation and fluctuation of the distribution network will be caused by the fluctuation of photovoltaic output and the uncertainty of load.At the same time,the unreasonable selection of the grid connection location and capacity of the distributed power generation will give rise to the voltage fluctuation,power deviation and growing investment cost of the distribution network.Therefore,how to optimize the configuration of photovoltaic junction capacity and reactive power control of grid connected system has become a research focus of distributed photovoltaic grid connected.Firstly,by analyzing the single distributed photovoltaic grid connection,the impact of photovoltaic grid connection on the voltage and harmonic injection of distribution network is studied,and then the RBTS96 test system is used to study the impact of the grid connection position and photovoltaic power capacity of distributed photovoltaic power supply on distribution network,the Simulink simulation model of PR controlled grid connected inverter is established,and the grid connected current and harmonic characteristics are analyzed through the simulation waveform.It is proved that the PR control used in this paper has high accuracy and dynamic response speed under the condition of constant and sudden change of power grid.Secondly,the multi-target fitness function including investment cost,voltage stability and power loss and the optimal allocation model of constraints are established;The sensitivity index is analyzed and determined as the basis for the candidate nodes of distributed generation.An adaptive SVM-MODE hybrid intelligent algorithm based on chance constrained programming is proposed.The IEEE33 node system is used for simulation research.The simulation results show that it can obtain higher power quality at low cost.Finally,a grid connected inverter control strategy based on SVM-MODE is proposed.Taking IEEE33 system as an example,it is obtained that the adaptive SVM-MODE algorithm can obtain a uniformly distributed Pareto front boundary width,which is wider than other algorithms,and the solution has higher coverage.The voltage amplitude and network loss of grid connected nodes under constant and changing light intensity are simulated respectively,which proves that this control strategy can more effectively reduce network loss and voltage deviation.