Patent ID: 9720027
Date: 2017-08-01
CPC Classifications: G01R,H02H

Claim:
1. A fault point locating method of hybrid lines based on analysis of comprehensive characteristics of single-end electric quantity and transient travelling waves, the method comprising: step 1, performing, by a computing device comprising a processor and a memory, phase-model transformation based on the single-end electric quantity, and reducing effect of inter-phase coupling of the transient travelling waves on section locating; step 2, utilizing, by the computing device, wavelet transformation to detect a signal break point of transient voltage and current travelling waves as the initial time of failure; step 3, extracting, by the computing device, timing window data after the initial time of failure of the voltage and current travelling waves, wherein size of the timing window is determined by cable length; step 4, searching, by the computing device, all reflected wave heads with the same voltage/current polarity and close amplitudes in the timing window, and computing relative values u step 5, judging, by the computing device, properties of the reflected waves; wherein, in step 5, supposing time of an initial fault wave as T when the fault point is located in the overhead line segment, the condition of the following formula (3) is satisfied: when the fault point is located in the cable segment, the condition of the following formula (4) is satisfied: and automatically switching-ON or switching-OFF of reclosing associated with the hybrid line based upon location of the fault in the overhead line segment and the cable segment, respectively, of the hybrid line.