中文摘要：

针对谐振接地系统单相接地故障，基于瞬时功率理论，提出了采用瞬时零序功率的复合选线新方法。，分析了系统故障后的稳态及暂态故障特征。利用坐标变换后的故障信号分别推导、计算了稳态和暂态过程线路上的瞬时零序功率。通过对瞬时零序功率的分解得出．故障前后线路上的零序功率振荡分量以及故障线路与非故障线路零序功率振荡分量成分不同、频率特征不同。通过提取并综合分析振荡分量中单倍、2倍、4倍以及6倍工频振荡信号来甄别故障线路。该方法综合暂态和稳态特征、考虑谐波信号、多判据互补、不涉及相位分析．并且物理意义清晰。仿真及实录数据验证表明该方法有效。

英文摘要：

A composite method of faulty line selection using instantaneous zero-sequence power is proposed for the single-phase-to-ground fault of resonant earthed system,and its steady-state and transient charac- teristics are analyzed based on the instantaneous power theory. The fault signals after coordinate transformation are used to calculate the instantaneous zero-sequence power of faulty circuit,which is then decomposed to extract its oscillating components. Because the oscillating components of faulty line are different from those of healthy lines,the oscillating components with one,two,four and six times of elementary frequency are picked out and comprehensively analyzed to detect the faulty line. This method integrates the transient and steady-state characteristics of fault and includes the harmonic signals. With clear physical meaning,it adopts multiple complementary criteria and avoids the phase analysis. Its validity is verified by simulation and field test.