Studying short-circuits in a 0.4 kV electric network using the ENGEE simulation environment

Modeling is one of the most effective ways to study the operation of technical systems. In recent years, a domestic modeling environment, Engee, has been developed, which is an analogue of MATLAB Simulink. Many scientific papers that use the Engee modeling environment are aimed at studying control processes, mechanization of production and other issues. However, works related to the modeling of electric power systems are absent. In this paper, a study of stable short-circuit modes in a 0.4 kV electric network is implemented. The prototype of the computer model of the 0.4 kV electric network is a 0.4 kV radial transmission line with a length of 1000 meters, made using uninsulated A-35 wire, connected to a TM-250/10/0.4 kV Y / Yн-0 transformer. Short circuit modeling was implemented at its most remote point at the consumer's input. The simulation time in the Engee environment was set to 0.5 seconds. Current and voltage distribution graphs were obtained for stable fault conditions, consistent with the theory of transient processes in electrical networks. It was found that in single-phase short-circuit mode, the voltage at the fault point is 0 V, and the current in the faulted phase significantly exceeds the currents in the undamaged phases. In two-phase shortcircuit mode, the voltages of the faulted phases are half their nominal voltage under load conditions, and the currents in the faulted phases increase significantly. In two-phase short-circuit mode to the neutral conductor, the voltages of the faulted phases at the fault point are 0 V, and the currents in the faulted phases increase significantly. Moreover, in three-phase short-circuit mode, the voltages of the faulted phases at the fault point are 0 V, and the currents increase and have the same values.