MODELING POWER SUPPLY SYSTEMS WITH THREE-PHASE AND SINGLE-PHASE CONVERTERS

Abstract

The PURPOSE of the paper is development of methods and tools for adequate modeling of electrical power supply systems equipped with three-phase and single-phase transformers. METHODS. The methods of electrical power system (EPS) simulation in phase coordinates based on the models of elements in the form of lattice equivalent circuits with fully-meshed topology are used for mode determination of electrical power supply systems equipped with three-phase and single-phase transformers. The models and methods are implemented in the program complex Fazonord. RESULTS. The models of three-phase and single-phase converters by Steinmetz, Terekhin and Sinev circuits are provided in the article. It is shown that Steinmetz converters have the potential of balancing both two-phase and single-phase load. This allows simultaneous compensation of reactive power and complete use of three-phase transformer resources in case of such load connection. Terekhin’s curcuit is a standard capacitor scheme used for supplying low-power three-phase motors from a single-phase network. This circuit creates significantly asymmetrical system of three-phase voltages as a result acceptable asymmetry levels can be obtained only under certain conditions. Sinev's circuit provides good balancing adjustment, but the levels of voltages strongly depend on load currents. CONCLUSION. EPS mode determination introduced by Irkutsk state transport university allows to simulate electrical power supply systems equipped with three-phase and single-phase converters.