Accurate positioning in the case of failure of single core power cables,as one of the channels for energy trans-mission in the auxiliary power supply system of electric multiple units(EMU),is of paramount importance in mainte-nance procedures.Currently,the widely adopted method for cable fault location is the time-frequency domain reflectome-try.However,the cross terms generated by time-frequency analysis limit the accuracy of fault location.Thus,Wigner-Ville distribution based on adaptive threshold segmentation was proposed in this paper.To begin,four types of fault sam-ples,namely low resistance,high resistance,open circuit and short circuit,were embedded into a 70-meter cable sam-ple.Subsequently,Wigner-Ville distribution transformation was used to process these detected signals to explain the rea-son for the cross terms generated,leading to the proposal of the Wigner-Ville distribution based on adaptive threshold segmentation to mitigate cross-term.Finally,a comparative evaluation was performed between the new method and exist-ing cross-term suppression methods.The results show that the proposed method that effectively eliminates cross-terms is applicable to both single-fault and multi-fault cable.The positioning error for single-fault location is below 0.80％and that for dual-fault is less than 0.40％,validating the effectiveness of the method presented.
关键词
电缆绝缘/缺陷与故障定位/时频反射法/交叉项消除
Key words
cable insulation/defect and fault location/time-frequency reflectometry/cross term elimination
维普
万方数据