FAULT-SECTION IDENTIFICATION FOR SINGLE-LINE-TO-GROUND FAULT HAPPENED IN HYBRID DISTRIBUTION LINES ON NONE-EFFECTIVE GROUNDING SYSTEM BASED ON MORPHOLOGICAL SPECTRUM

Hongchun Shu ； Zhen Gong ； Xincui Tian

《電機工程學刊》 26卷1期 (2019/02) Pp. 15-24

https://doi.org/10.6329/CIEE.201902_26(1).0003

摘要

In order to solve the problem of low accuracy of fault section identification when a single-line-to-ground (SLG) fault occurs in hybrid distribution line, which is an overhead line combined with an underground cable. Especially for high impedance grounding faults or small fault inception angle faults, the paper presents a single-ended morphology spectrum based faulty section identification method for the hybrid distribution line. The new method uses only ground mode currents extracted from fault line for fault section identification when a fault occurs in underground cable or overhead line, and the amplitude and phase differences of the currents caused by different fault locations are analyzed and characterized by morphological spectrum which avoids the using of low accurate traditional method of catching traveling wave's arrival time. Obtained results of simulation of 35kV hybrid distribution lines of distribution system based on PSCAD/EMTDC and MATLAB show the methods can reliably recognize the section of SLG fault.

關鍵字

fault section identification ； none-effective grounding system ； morphological spectrum ； ground mode current ； SLG