The connection of DG transforms topology structure of traditional distribution network, power flow direction and fault current changes in real time with DG contributions and load conditions. These factors will bring serious influence on three-phase current protection of prevailing system. As DG quantity grows and penetration rate improves, protection algorithm relying on the single point fault information can’t meet the four basic requirements of relay protection simultaneously. So that, this paper introduces a new regional protection scheme based on communication technology. The distribution network should be divided into distinct regions. The protection algorithm is composed of two steps:first and secondary fault locating to discover the fault section and achieve protection. We can utilize fault current positive-sequence component information from Bus-IED in substation and A-IEDs in feeder during fault periods to achieve first fault location, then take advantage of break-variable of current information from A-IEDs or B-IEDs after the corresponding breaker action to realize secondary fault location. In this scheme, adaptive region division has features of simple algorithm, small storage space, easy realization and good visibility. The advantages of fault location are little information, high reliability and good adaptability. Finally, simulation results from PSCAD/EMTDC verify the correctness of the method.%分布式电源（DG）的接入改变了传统配电网的拓扑结构，网络中潮流方向及短路电流会随着 DG出力及负荷情况实时变化，这都给现有配电网的三段式电流保护带来了严重影响。随着 DG的大量接入及渗透率的提高，依靠单点故障信息的保护算法很难同时满足继电保护四性的要求。提出一种基于通信技术的区域保护新方案，对配电网进行区域划分，通过一次和二次两步定位确定故障区域实现保护。利用故障时变电所母线处Bus-IED（智能电子装置）及馈线上A类IED的故障电流正序分量信息完成一次定位；利用相应开关动作后A类IED或B类IED处的电流突变量信息实现二次定位。所提方案自适应区域划分算法简单，占用存储空间小，实现方便，直观性好。故障定位所需信息量小，可靠性高，适应性强。最后通过PSCAD/EMTDC仿真，验证了方案的正确性。
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