The Research Of Fault Location Basecd On Power Quality Monitoring System For Smart Grid

With the development of the concept of the global energy Internet,the development direction of the intelligent and global grid is determined,and the requirements of power quality,reliability and intelligence are more stringent.Therefore,the reliability and power quality should be put in the important position in the construction of modern smart grid.One of the main features of smart grid is the wide application of the monitoring device and a large amount of field data.This makes the Power Quality Monitoring System(PQ)and Distribution Supervisory Control and Data Acquisition(DSCADA),Phasor Measurement Unit(PMU),the Advanced Metering Infrastructure(AMI)of PQ monitoring network racing together bridle to bridle.It is the trend of the development of the field of call quality in recent years to study the information contained in these data.In this paper,the PQ parameter is applied to the fault location to solve the problem of power supply reliability.It is a bold attempt for the new application of PQ monitoring system data.In this paper,the traditional fault location methods are introduced,including active fault location method and passive fault location method,and their advantages and disadvantages are summarized.It provides reference and theoretical support for the realization of fault location.Then,the parameters of power quality are introduced in detail,and the method of voltage sag detection is deduced,and the voltage sag signal is generated and detected by LabVIEW.The simulation results prove the validity and accuracy of the DQ decomposition method for voltage sag detection,which provides a reliable basis for the fault location of the PQ using the important disturbance information voltage sag value.Then,in order to make full use of the data resources of the PQ system,a practical location algorithm based on the voltage sag value and the fault distance distribution function is proposed.Firstly,the distribution function of the monitoring point voltageOn the fault distance is established by the node impedance matrix,and the location of voltage sag monitoring point is configured.Then the measurement parameter matrix is established.When the fault occurs,the fault line and fault distance can be determined by establishing the state vector of the monitoring point.This method is simple in principle,does not need iterative calculation,and can achieve real-time fault detection and location.Finally,an example of a 10 node ring distribution network is analyzed by MATLAB.Finally,the effectiveness of fault location by using the voltage sag value is verified.Finally,the power quality monitoring system and fault location device with voltage sag detection and voltage sag source location function are developed by Lab VIEW.In this paper,the hardware structure,software composition of power quality and the basic process of fault location are introduced.Finally,through the realization of Lab VIEW monitoring of power quality parameters,and realize the location of the voltage sag source,provides the basis for the sag responsibility quantization;in addition to achieve the function of fault localization,to timely troubleshooting,can improve the reliability of power supply.In this paper,using only the amplitude information of voltage sags,it can locate the fault point,the data at the same time there is no requirement,and can effectively use the existing device,realize the economic construction of monitoring network and fault location system.At the same time,it is necessary to explore the other data resources of the power quality monitoring system,and the construction of the communication network and the data transmission format of the fault location need to be further explored and studied.