超高压输电线路故障波形特征分析

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中图分类号：TM711 文献标志码：A 文章编号：1003-5168(2025)19-0005-04

DOI:10.19968/j.cnki.hnkj.1003-5168.2025.19.001

Analysis of Fault Waveform Characteristics in Ultra-High Voltage Transmission Lines

LIN Sheng (Ultra-High Voltage Branch,State Grid Fujian Electric Power Co.,Ltd.,Fuzhou 35OO01,China)

Abstract: [Purposes] To deeply analyze the fault waveform characteristics of 500kV ultra-high voltage AC transmission lines and establish an eficient fault identification method.[Methods] Firstly,a method combining digital simulation with actual data was adopted to analyze the waveform characteristics of typical faults,including single-phase grounding,phase-to-phase short circuit,metallic short circuit, and non-metalic short circuit. Secondly,through time-domain and frequency-domain feature extraction, typical fault characteristic parameters were selected. Thirdly,a complete 500kV transmission system model was built using the PSCAD/EMTDC platform,and the configuration of the main system equipment was measured.Finally,a hybrid algorithm combining deep learning and traditional machine learning was used for fault identification,and the identification results were analyzed.[Findings] Different faults have unique waveform fingerprints: the current of a single-phase grounding fault reaches 8~12 times the normal value, with frequency concentrated in 1~3 kHz; phase-to-phase short circuit current reaches 15~20 times; metallic short circuit voltage drops to zero within miliseconds;and non-metalic short circuit exhibits a three-stage characteristic.Tests on1,OOo data sets show that the proposed method achieves an identification accuracy above 96.8% ,withan identification time within 1O ms.[Conclusions]Fault waveform characteristic analysis provides an important basis for ultra-high voltage line protection.The hybrid algorithm significantly improves fault identification accuracy,meeting real-time protection requirements. Keywords:ultra-high voltage AC transmission line;fault waveform;characteristic analysis;fault identification;digital simulation

0 引言

随着电力系统规模的不断扩大和输电电压等级的持续提升，超高压输电技术在远距离、大容量输电中发挥着越来越重要的作用。（剩余6204字）