This paper presents a study of the approaches taken to model and simulate power systems of an industrial plant. Even the best-designed electric systems occasionally experience short-circuits resulting in abnormally high currents. To predict the behavior of these short circuits, system models are developed and simulated prior to commissioning work in the plant. Mathematical modeling of each component in the power system is based on short-circuit analysis techniques which are covered extensively throughout this paper. From the models and parameters developed we can calculate fault currents in a power system, which is the main emphasis in this study. Digital simulation is carried out using the Power Systems Blockset (PSB) of MATLAB, which is a powerful graphic tool that allows building of schematics and real-time simulation of power systems in the Simulink environment. Finally the calculation and simulation results are compared to validate the accuracy of the model. © 2002 IEEE.