Power generation becomes a main way of using new energy. However, the access of distributed generation(DG) causes the ordinary protection system develop a series of problems. In this paper, the structure of distribution network with DG is introduced firstly.Secondly,it is analysed that the effect that DG brings to distribution network protection, and then a new protection scheme of distribution network with DG is put forward. The segment I, II of direction three-current protection on the line which is at the upstream of DG, and the next line’s segment I, II consists of a simple communication unit. Through the comprehensive judgment of two protections’ action results, fault can be isolated in minimum range quickly and accurately. Finally, the correctness and feasibility of the new protection principle are verified by simulating a 10KV distribution system.
