中文摘要：

对--800-kV直流输电线路区内及区外故障分量附加网络的理论分析表明,当直流输电线路发生区内故障时,于故障启动元件响应之后的短数据窗内,线路两侧电压电流故障分量均满足平波电感元件性能方程（voltage current relation,VCR）;当发生区外故障时,故障侧的电压电流故障分量则不满足平波电感元件的VCR。为此,提出了基于实测电压与计算电压相关性的区内外故障判断方法：直流线路发生区内故障时,运用线路两侧实测电流由平波电感元件VCR分别计算两侧的电压,计算所得的电压波形与实测电压波形正相关,且数值很大;发生区外故障时,则故障侧计算所得的电压波形与实测电压波形负相关。据此,利用线路两侧计算的电压波形与实测电压波形的相关系数构造区内外故障识别判据。仿真结果表明,该识别算法可灵敏区识别内故障并可靠识别区外故障,可用于加速直流输电线路的后备保护动作。

英文摘要：

The theoretical analysis about the fault component network with the internal and external faults at 800 kV HVDC transmission lines show that,the relation between the voltage fault component and the current fault component is inductor voltage current relation（VCR） in the short data window after the fault start-up element response the internal fault;In the external fault,the relation between the voltage fault component and current fault component is not the inductor VCR at the fault terminal.So this paper put forward a method based on the correlation between the calculation voltages and the measured voltages to identify the internal faults and external faults.If the internal fault occurs,the voltages can be calculated using the currents of both terminals according to the inductor VCR.The waveforms of the calculated voltages have positive relation with their responding measured ones and the correlation coefficient has a great value.While for external faults,the two waveforms have negative relation.Thus the correlation coefficient can be applied to construct the criterion to identify between internal faults and external faults.Simulation results show that the algorithm is sensitive to internal faults and reliable to external faults.It can speed up the backup protection of DC transmission lines.