Short-circuit current calculation of distribution network with distributed generation

The distributed generation integration to the distribution network would have some influences on short-circuit current level. According to the short-circuit current characteristics of the generator-based distributed generation and inverter-based distributed generation, their equivalent circuit during the short-circuit has been obtained. All of the power sources including the distributed generation should be substituted with equivalent current sources, and the fault equivalent circuit should be decomposed into a normal component network and a fault component network. The normal component and fault component of the short-circuit current can be calculated with the node voltage equations, and then any case of fault current in the distribution network can be solved with this method. Through comparison with and analysis of the testing results on a typical system, it is shown that the proposed method is efficient and accurate. This method can be applied to short-circuit current calculation of large-scale distribution network with computer. ©, 2015, Power System Technology Press. All right reserved.