中文摘要：

利用微分算子的代数逼近，将线路的电报方程进行变换解耦，得到时域内电压、电流随距离分布的解析解，发现线路沿线分布电压的差分在一个时间段内的能量在故障点呈现最小值，据此构造了新的故障测距函数。通过证明，利用单端量计算得到的“虚假”电压分布与真实电压有相同的分布规律。进而提出了一种基于微分算子逼近的单端故障测距新原理。同时，详细阐述了三相故障测距新算法。EMTP仿真验证了单端故障测距新原理的准确性和正确性。

英文摘要：

Based on application of differential projection operator for solution of distributed parameter telegraph equations of the line, a novel principle for the single-ended fault locating is proposed. According to the analytical solution, a new fault locating function is constructed, which has only a minimum value at the fault point. Whilst, the fault locating functions calculated with real voltage value and with fictive voltage have similar distribution. Hence, the fault can be determined by utilizing the fictive single ended datum, combined with the fault locating function. Then three-phase fault locating algorithm is described in detail.The property and accuracy of new fault locating principle is verified with EMTP simulation tests.