Research Of Distribution Network Fault Location System

Timely detection and accurate location of distribution network faults can effectively improve the reliability of power supply.At present,China’s power grid is in the phase of upgrading,and the coexistence of new and old equipment and lines increases the difficulty of power grid fault identification and location.In this thesis,a new miniaturized fault location system is designed on the basis of analyzing the disadvantages of traditional fault location devices and combining with the current advanced technology.The innovation of the system lies in that it considers the influence of distributed power supply on fault location system.It adopts communication method and passive detection method to realize isolated island detection of distributed power supply.It uses 4G wireless communication to realize remote data communication.It uses ZigBee wireless communication to realize interphase communication.It realizes fault identification and location by real-time acquisition of line voltage,current,frequency,phase and other parameters.(1)Based on the analysis of the working principle of the fault indicator and the basic characteristics of the distribution network fault.It puts forward the basic method of fault judgment according to the performance of electrical parameters,and focuses on the influence of distributed power supply on fault location.(2)It puts forward the functional requirements of fault location device according to the basic requirements of current power grid development.The fault location system is divided into three parts:background server,terminal detection device and data communication.It innovatively proposed the islanding effect detection strategy based on communication method and passive detection method,and designed the islanding detection process.(3)It determines the distribution network fault information collection design scheme including distributed power.It focuses on the hardware unit design of fault location device.It uses RN8209 chip to realize real-time measurement of voltage,current,frequency and other parameters.It adopts WH-G401TF module to achieve 4G wireless communication and GPS positioning and timing information acquisition.It adopts transformer power supply and battery power supply to achieve reliable power supply.It uses ZigBee module to realize data communication between three phases.It uses STM32F103 controller as the core controller of fault location device.(4)It finally completes the software design and system test of fault location device.It adopts modular programming to design different subroutines according to different functional units to facilitate the management of the system.On the basis of analyzing the basic function test of hardware platform,it completed the test of 4G wireless communication and electrical parameter acquisition function.Through the actual test system function realization,the performance is good,well realize the fault identification and location.