Research On Key Technologies Of Cable Network Fault Location

With the accelerated pace of urbanization construction, cable play a important role in the construction of grid construction. In large and medium-sized cities, cable network has become the dominant form of power supply network. The research on operation mode of cable network and cable faults, and related problems, it is particularly important.Single-phase ground fault is one of the most common faults in cable network, and it is about 80% of the total faults, and most of the faults are caused by the single-phase ground fault. Therefore, the research on key technologies of fault location in cable network is proposed, it has the great significance for the cable network to be stable, healthy, safe operation.In this thesis, 10kV neutral grounding via arc suppression coil in ground distribution network is used to illustrate how to use existing theory and methods quickly and accurately select the fault line and measure distance accurately when the single-phase ground fault occurs. Firstly, ATP software is adopted to establish and simulate of the system in order to provide the data of fault analysis. Secondly, MATLAB software is applied to analyze data for the fault line and measure distance because of its powerful data processing ability and wavelet time-frequency localization characteristics. By analyzed and summarized, a fault line selection method that based on transient population amplitude and phase method, supplemented on the transient energy method is presented, according to the different polarity and the amount of energy to fix the fault line. In aspect of fault location, the research is focus on the single-ended traveling wave method and double-end traveling wave ranging method, using the reliability of double-end traveling wave ranging method and accuracy of single-ended traveling wave method to achieve fault ranging, comprehensive analysis of the two methods, it can achieve the purpose of ranging accuracy and reliability. The methods that proposed have great value for the research on fault location.