直流接地极线路故障暂态行波传播特性分析

高压直流输电系统接地极线路由于铺设的特殊性与复杂性，较易出现故障。介绍了接地极线路故障初始行波的产生机理，对接地极线路发生单线接地、两线短路和两线短路接地3种故障时的故障初始行波模量及其在直流中性母线端和接地极处的传播特性进行了详细的分析。以PSCAD/EMTDC为电磁暂态仿真分析平台，建立高压直流输电系统模型，通过高压直流输电系统单极大地回线模式下的接地极线路故障进行了仿真验证，仿真结果表明了分析的正确性。接地极线路故障暂态行波的传播特性分析为利用暂态行波实现接地极线路故障测距奠定理论基础。

Analysis of Propagation Characteristics of Transient Traveling Waves in HVDC Grounding Electrode Line Faults

HVDC grounding electrode line faults tend to happen due to the specificity and complexity of line laying. In this paper, the mechanism of the traveling wave initiated by the grounding fault is introduced. Then the detailed analysis on the traveling wave modulus and the transmission characteristics in the DC neutral bus and the grounding electrode is conducted in terms of single line to ground fault, line to line fault and double line to ground fault, respectively. Based on the PSCAD/EMTDC electromagnetic transient simulation platform, the HVDC system model is established, in which the grounding fault in the single-pole grounding metal line mode is simulated and verified. The simulation results show the validity of the analysis. The analysis on the grounding fault and the propagation characteristics of the transient traveling wave can provide a theoretical foundation for grounding fault location by adopting transient traveling wave.