Research On Fault Location Method For Transmission Line

In order to realize the grand goal of “Chinese dream”, our country has made a greatprogress in economy, industry, agriculture, national defense, science and technology. At thesame time, people’s living standard has been greatly improved. All of these achievements arebased on preferential development of electric power industry. The demand for supply andreliability of power is becoming higher and higher. Besides, the uneven distribution of energysupply and demand in our country leads to the development trend of ultra-high voltage, longdistance, large capacity transmission in electric power industry. However, transmission line isone of the power system equipments which malfunction occur very frequently. In order totroubleshoot rapidly, restore power supply quickly and reduce the outage costs, it is veryimportant to locate the fault rapidly, accurately and reliably.Firstly, the thesis summarizes the research status of fault location methods fortransmission line at home and abroad. And then, a new one-terminal fault location methodapplied to common transmission line is proposed. Taking the system conditions and faultparameters as extended system states, the fault distance can be calculated by the data of10msbased on the STF after fault happened. Moreover, the thesis proposes two-terminal faultlocation method applied to transmission line with series compensator. Based on the STF, themethod needs the data of voltage and current at one end and current at the other end to locatefault. Besides, two methods based on wavelet analysis and dispersion are proposed torecognize whether the fault occurred ahead or behind the series compensator.With the purpose of checking the accuracy of these fault location algorithms,transmission line simulation models are built in PSCAD/EMTDC to collect fault data. Andsecondly, MATLAB is used to write STF recursion program, which can analyze the fault dataand locate the fault. A large number of simulation shows that the two methods are simple andable to accurately locate the fault in various fault modes and are free from the influence of random factors such as fault transition resistance and fault inception time.