Load flow analysis in alternative tools using equations, physical and block diagrams

This paper describes the load flow analysis and its solution in alternative tools using physical and block diagrams. Usually, each load flow problem is defined for one phase only and solved by the respective system of equations. Using the physical diagrams, load flow problems can be analyzed for all three phases by considering phase-to-phase and phase-to-earth couplings, which are normally included only into one-phase parameters. By this approach, more detailed outputs in the form of voltage magnitudes and phase angles in individual buses of the examined power system can be obtained. As the first alternative tool, simulation software DYNAST was selected due to its constantly growing libraries of network models and hence, with real potential for performing a broad variety of simulations in the field of power engineering. The second alternative tool examined is MATLAB Simulink. For comparison purposes, PowerWorld Simulator and SimEPS tools are used for providing highly accurate load flow solutions. Main goal of this paper is to evaluate the reliability of results and especially the benefits of modelling one- and three-phase load flow problems using physical diagrams.