General Analysis and Calculation Method of Asymmetric Short-circuit in Distribution Network Considering Two Short-circuit Points

In the new type of distribution networks, in which inverter-based distributed generation (IBDG) is widely used, the main methods to calculate asymmetric short-circuit current always focus on a single short-circuit point and have low universality to process a newly added short-circuit point. A novel asymmetric short-circuit current calculation method for distribution networks is studied. This method further classifies asymmetrical short circuits by taking two short-circuit points into account, and the universal equivalent circuit of asymmetric short circuits combined with the equivalent circuit of IBDG is formed. Then, the calculation and boundary equations of 1 and 2 short-circuit points are established, respectively, and a general asymmetric short-circuit current calculation method is proposed, which can account for 2 short-circuit points for the distribution network universally. Finally, the proposed method is verified in a distribution network example, and the results show that the proposed method is correct and effective.