In a distribution network system composed of DG, current protection is usually adopted as its main protection. The setting value of current protection is a fixed value. With the access of DG, the structure of the network changes. Different locations of DG merging into it will bring the problem that the fault point cannot be accurately determined. In response to this, we propose a communication-based fault location scheme. It introduces directional components to detect the current flow to accurately determine the location of the fault point. The difference in DG access capacity and the change in the current value sent by DG before and after the fault cause an original current protection mismatch in the distribution network. We propose an improved adaptive overcurrent protection algorithm. By detecting the fault current positive and active sequence components, it determines the type of fault, and then uses different setting values, so that the setting value of current protection changes at any time, enhancing the reliability of protection action. The above strategy is verified by PCSAD/EMTDC simulation and experiment and shows that the proposed scheme can effectively improve the accuracy of the protection action brought by DG grid connection. This work is supported by the Youth Fund of National Natural Science Foundation of China (No. 51807114).