中文摘要：

针对传统距离保护方案抗过渡电阻能力差的问题,提出了一种基于阻抗复数平面的自适应距离保护方案。首先,利用保护安装处负序电流与故障点电流间的相位关系,计算过渡电阻引起的故障附加阻抗角;再根据测量阻抗、故障附加阻抗和有效故障阻抗在阻抗复数平面上的几何分布关系,求解故障点到保护安装处的有效故障阻抗;在此基础上,构造了自适应四边形阻抗继电器动作方程。基于实时数字仿真（real time digital simulator,RTDS）平台的仿真结果表明,所提方案适用于阶段式距离保护,且不受故障类型的影响;与传统距离保护方案相比,具备更强的抗过渡电阻能力,可有效解决过渡电阻引起的距离保护超越或拒动问题。

英文摘要：

In view of poor immunity of conventional distance protection scheme to transition resistance, a distance protection scheme based on impedance complex plane is proposed. First, phase angle of fault supplementary impedance caused by transition resistance is calculated with phase relationship between measured negative sequence current at relay and fault current. Then, according to geometric distribution characteristics of measured impedance, fault supplementary impedance and effective fault impedance in impedance complex plane, effective fault impedance from fault point to relay is obtained. On this basis, operation equation of adaptive distance protection with quadrilateral characteristic is established. Simulation results based on RTDS（Real Time Digital Simulator） show that the proposed scheme is suitable for stage distance protection, and immune to transition resistance. Compared with conventional distance protection scheme, the proposed scheme has stronger immunity to transition resistance and can effectively solve mal-operation or misoperation problem of distance protection caused by transition resistance.