Study Of The Device For Fault Location Of Over-head Transmission Line On Two-terminal Synchronous Data

When faults occur in the transmission line, locating the fault accurately and timely is propitious to eliminate the fault and restore power supply.The main contributions of the dissertation are as follows: it study the part of data sampling of fault location device, and introduce a new algorithm for fault location based on two-terminal asynchronous data, finally a set of device for fault location of the transmission line is developed. Based on the integrate analysis of the application status and the existed problems of transmission line fault location, the dissertation presented firstly to correct data after fault by the integrate error correction method, then to locate fault distance. EMTP program shows that this algorithm can improve the accuracy of fault location evidently in contrast with other methods.Simultaneity, some protective algorithms ate discussed in the dissertation, improved on using single algorithm in both record star-up and the extraction of fundamental frequency component in location. The Whole-cycle Fourier differential algorithm is adopted in record start-up to satisfy the real-time requirement. The least squares method is applied to extract the fundamental frequency component in location which has low computing speed but high precision. The software of the device is developed using Delphi 5.0 environments, which can control the data acquisition, finally the fault distance are presented, which make the device a rounded system.