Research On Distributed Traveling Wave Fault Location Technology For High Voltage Transmission Lines

With the extensive interconnection of China's power grid and the large increase in transmission capacity,the advantages of high-voltage transmission lines in grid interconnection and long-distance transmission have become increasingly prominent.It plays a very important role in the nationwide network,the transmission from west to east,and the transmission from north to south.However,power system failure is difficult to avoid during the operation of the power system.Especially in high voltage transmission lines,due to its long transmission distance,the weather and environment along the way are complex and variable,and it is easy to cause lightning,discharge,short circuit and other faults.After the fault occurs,the fault point is extremely difficult to find,which causes the line to be forced to power out for a long time,which seriously affects the reliability of the power supply and causes huge economic losses.According to the fault characteristics of high-voltage transmission lines,a distributed fault location system combining non-contact wide-band traveling wave acquisition,high dynamic range transient signal processing and distributed traveling wave ranging algorithm is constructed.It is possible to further improve the accuracy of fault location,achieve reliable and accurate fault location,improve the quality of the line,and reduce the working intensity of the line.Based on the distributed contactless acquisition terminal,the system simulates the space electromagnetic field sensor.Using the GPS synchronous clock technology and the time compensation deviation algorithm,the time deviation caused by the compensation is compensated,and the time precision is improved.In this paper,the adaptive traveling wave ranging algorithm and the wide dynamic range transient impact starting algorithm are combined to establish a realistic distributed traveling wave ranging model to realize the non-contact acquisition of traveling wave signals.It has high resolution and acquisition capability for weak traveling wave signals generated by high-resistance faults,which can greatly improve the accuracy and reliability of traveling wave ranging.Based on the non-contact traveling wave acquisition technology,this thesis develops a non-contact traveling wave positioning terminal device,which realizes high-speed acquisition,recording and remote transmission of traveling wave signals.The positioning terminal is distributed and installed on the line pole,and it is not necessary to be powered off,and the operation management and maintenance are convenient.In addition,this paper also designed the software and hardware functions of the system to form a complete distributed fault location system.Through the actual test,the correctness of a series of data processing channels such as synchronous data acquisition,data processing,data storage and data transmission in the trigger state of continuous random signals is ensured,and the conditions and requirements for accurate ranging of on-site faults are met.It provides powerful technical support for finding fault points on high voltage transmission lines,analyzing fault causes and quickly recovering power supply.