Research On Access Mode And Fault Location Of The Grid-connected Photovoltaic System

The grid connected mode and fault location of photovoltaic system is of great significance to the stable operation of the system.The optimization of grid connected mode of photovoltaic system can improve the reliability of power supply,which makes the rational allocation of resources and raise the level of power supply,andbring economic benefits.The accurate location of the fault after grid-connected photovoltaic system can improve the stability of the system and reduce the economic loss.In this thesis,firstly I analyzed the influence of grid-connected photovoltaic system.On the basis of the analysis,I analyzed and summarized the access mode and fault location of grid-connected photovoltaic system.I analyzed the equivalent model of distributed generation in detail.The equivalent model of the solar photovoltaic power generation system is built with the actual project.It is proved that it is equivalent to the voltage source.Taking the grid-connected photovoltaic system as an example,the different effects of the different capacity of the distributed generation supply on the system are analyzed.I carried out the modeling and simulation on the basis of theoretical analysis.Based on the help of distributed and the role of the shunt,I get an optimal access mode of grid-connected photovoltaic system with universal applicability.On the basis of theoretical calculation and analysis,I used the PSCAD/EMTDC simulation software to verify the correctness of the method.The optimal access method has a strong applicability for different access points and the different capacity of grid-connected photovoltaic system.I obtained a fault location method based on wide area node search after analyzed the influence of grid-connected photovoltaic system on the traditional fault location,and verified the accuracy of the fault location method by the IEEE33 node distribution network.The grid-connected photovoltaic system single point access and multi access are verified,and the results show that the proposed method is suitable for the different situations of grid-connected photovoltaic system integration.