Design And Implementation Of The Distributed Transmission Line Fault Location

With the increasing of transmission capacity and the rising of voltage grade of transmission lines, transmission line faults will not only harm the secure and stable operation of power system but also affect the living of societal economy and polity. Consequently, it becomes more and more important to rapidly and accurately determine the fault point according to different fault feature, which can not only restore power supply quickly, improve the reliability and safety of the overall power system, but also save much manpower and material of line-tracking. Therefore, it is of great social and economic benefits.At present, fault location device of transmission line mostly use traveling wave location method, including two-terminal and single-terminal fault location method. As for traveling wave signal acquisition, voltage and current transformer that already in substation are mostly used. But traditional transformer has some drawbacks, such as much narrower frequency range, easy to saturate, poor high frequency response, ect. Therefore, it's not easy to detect the transient traveling wave, hence, affects the location precision.In first two chapters, the commonly used method and develop situation of transmission line fault location is comprehensive analyzed and summarized, and then compare the advantages and disadvantages of various location methods and their applications. Based on traditional traveling wave location method, this paper poses a distributed traditional raveling wave location method.The third and fourth chapter mainly introduced the hardware design of fault location device, particularly about the fault current data acquisition unit, which including current sampling channel of Rogowski coil based on no hysteresis, high linear degree and good transient response, high-speed data acquisition and storage unit, transient traveling wave sampling trigger unit.In the fifth chapter, software design of fault location device is comprehensively researched. The wavelet transform theory,espceially the singularity-detected theory is diseussed in this chapter. As for the detection of singularity and traveling wave head, the modulus maxima line is used.In the last chapter, a series of experiments is made to analysis the existing problems under real working condition, and then some solving measures are proposed. Finally, research results of this paper are summarized and based on present research some improvement is put forward.