Abstract:In view of the problem that the traditional current protection method cannot be applied when distributed generation (DG) is connected to the distribution network, this paper takes the double-feeder distribution network line as the research object. Firstly, when three-phase short-circuit faults occur at different locations of the line, the influence of DG connected to a busbar of feeder ends or a non-end busbar on the short-circuit current flowing through each protection device in the line is analyzed. Then, a distribution network model is built by PSCAD software for simulation analysis. Since it is difficult to set the action value of short-circuit faults in the distribution network containing DG, a matrix algorithm based on intelligent electronic devices (IEDs) for fault information uploading is proposed, and the accuracy of the algorithm is verified by an example. The results reveal that when DG is connected to a busbar of feeder ends or a non-end busbar, the fault that occurs in the downstream of DG will cause maloperation of the protection device in the fault section, and the protection device in the upstream section may encounter operation failure, which is not conducive to fault positioning and removal. The proposed matrix algorithm is applicable to the distribution network with DG, and regardless of single or multiple faults, the fault area can be accurately located to ensure the safe and reliable operation of the distribution network.