The Research Of Fault Section Location In Distribution Grid

With the requirement of the quality of power supply is higher and higher,as well as the distribution grid directly connected with the users,the reliability of the distribution grid has been paid more and more attention.If the distribution grid fails,the national economic loss will increase with the expansion of the scope and the power outage time.So when the distribution grid faults,it is very important to ensure the maximum reduction of the scope and duration of the outage.Distribution automation technology is a part of smart distribution grid technology,and it has received extensive attention in recent years.As the core of distribution automation technology,feeder automation technology is a practical technology to improve the reliability of distribution grid power supply.Firstly,the current and voltage information which is sent by the mutual inductor is collected by FTU,and then the information is sent to the main station of distribution automation through processing.The main station system analyzes and processes the information,and the effective control of the distribution grid operation is realized finally,which ensures the reliability of the power supply to the users.When the distribution grid faults,the distribution grid fault information sent by the FTU is analyzed and processed by the main station,which can quickly locates the fault section,isolates the fault section.Compared with the manual inspection method,this method greatly reduces the power cut scope and power outage time.Distribution grid fault section location matrix algorithm is based on the feeder automation technology.It needs to combine the matrix representation model of distribution grid topology and the distribution grid fault information sent by FTU,and finally uses the fault diagnosis principle to achieve the fault section location.The current matrix algorithm based on the digital information.Due to the complex structure of the actual distribution grid and the complex fault situation,accurate location of some types of fault conditions can not be achieved by the current matrix algorithm.Improved matrix algorithm is used in this paper,and the new principle of fault diagnosis based on digital information and analog information is designed.This algorithm greatly improves the accuracy of fault section location.Finally,the accuracy of the algorithm is proved by the analysis of examples and simulation result.As FTU is installed in the outdoor environment,the acquisition and sending of data is easy to be affected by environmental factors.The fault information of distribution grid which is received by the master station may be distorted,which will result in wrong location of fault section.In this paper,the fault information distortion repair method based on the back stepping method is used to restore the distortion information effectively.Finally,the practicability of the method is proved by the analysis of examples and simulation result.