Unsymmetrical short-circuit analysis for distribution system considering loads

•A method for short-circuit study of distribution system considering loads.•The method is applicable to radial as well as meshed distributions systems.•The method is capable of handling multiple faults.•The results compare extremely well with PSCAD/EMTDC simulations.

Short circuit analysis is an essential tool for determining the short-circuit-current rating of the protective devices and different substation equipments to be installed in a distribution system as well as for co-ordination of the protective devices. Usually, the effect of load is neglected during short-circuit analysis, which introduces inaccuracy in the calculated values of short-circuit current. To address this issue, this paper proposes an efficient and accurate short-circuit fault analysis method for balanced and unbalanced distribution system considering the effect of loads. Comparison of the results obtained by the proposed method with those obtained by time-domain simulation using PSCAD/EMTDC establishes the accuracy of the proposed method.