Steady State Condition of Cable Line 10 kV at Single-Phase to Ground Fault with Resistive Neutral Earthing

Abstract

The work is devoted to the study of the steady state mode of cable line 10 kV at single-phase short circuit and resistive grounding of the neutral. A model of a cable line, implemented in the MATLAB-SIMULINK package was used. Also the models of supply transformer and additional transformer for creation of artificial neutral point were used, based on available standard elements. So, the specifics of operation of additional transformer for creation an artificial neutral point and real parameters of the cable and transformers were taken into account. It is shown that in the resistive grounding mode the nature of the displacement of the linear supply voltages triangle at variation of the fault resistance differs from what takes place in the partial compensation and overcompensation modes. At single-phase short circuit and any value of fault resistance, the choice of the value of the resistor in the neutral significantly affect the magnitude of the current and voltage in it. However, the current and the voltage at the place of damage at large values of the fault resistance does not significantly depend on the value of the neutral resistor.