Research Of The Key Technology Of Cable Fault Measurement

Following the rapid development of economic and the increase of the urbanscale, the consumption of the electricity is increasing year after year. The security ofpower supply is becoming more and more important to ensure the city’s normaloperation. Considering the beauty of the city, cable is increasingly applied in urbandistribution network instead of overhead lines, cable is usually placed undergroundwhich is known as a harsh environment that augment the possibility of the fault. Inaddition to the complex magnetic environment, it means a lot to the stability of thepower application that a rapid and accurate way to measure the faults.Pulse source, recognition of the start point of the reflecting wave and faultmeasurement of cable connector are researched based on the Traveling-wavereflection method. First, pulse source is designed depends on the need of cable faultmeasurement. Second, improved weighting coefficient method which can improvethe SNR of reflecting wave are presented to proceed the reflecting signal to reducethe error of the recognition of the start point of the reflecting wave which canimprove the accuracy of recognition. The effect of this method is obvious, but itneeds a PC to process the data which is not suitable to the MCU. Curve fittingmethod is presented to solve this problem. Traveling-wave measurement method ispresented against the disadvantage of temperature method and partial dischargemethod. Related experiments are done.It provides a new way to measure the connector fault and widen the use rangeof travelling wave method on cable fault measurement. The problem of cable faultmeasurement is solved by this paper through the research of key technology of cablefault measurement. The method can improve the stability of the Power grid andprovide lots of support.