Physical Modeling of Distributed Electrical Supply Systems in Non-Phase Modes

The results of physical modeling of power supply systems with several stages of supply voltage transformation and symmetric three-phase load are presented. The results were obtained on the physical model of the power system made at Voronezh State Technical University. The physical model consists of the physical model of a power plant with different types of generators, physical models of transformer substations with transformers of various groups of windings, and physical models of overhead and cable power lines. A special group of models is made up of load nodes, including those with voltage regulation at the points of common coupling. The obtained at the points of common coupling electric power quality indicators are discussed for the devices with the systems “converter-frequencyasynchronous motor with squirrel-cage rotor The complex studies of the voltage form deviation from the sine and the degree of symmetry are of interest, taking into account the phase of the load, especially at non-phases modes from a high voltage side of main step-down substation of a power system. The conclusions are drawn about the need to change the approaches towards the fine-tuning of the settings of directional differential protection of power lines when non-phase modes occur.