COMPUTER SIMULATION OF THE SINGLE-PHASE SHORT CIRCUITS IN ELECTRIC NETWORKS WITH LOW-RESISTANCE NEUTRAL GROUNDING

Kudelina Daria V., Biryulin Vladimir I.

the article deals with the issues related to the operation of medium voltage cable electrical networks with low-resistance resistive grounding of the neutral, made by power cables with screens. The computer model created by the authors gives the investigation results. This model presents the voltages values arising on grounding devices in the event of a short circuit between a current-carrying core cable and a screen grounded on both sides. It is shown that the values of the voltage arising on the grounding devices can be dangerous. Designing medium voltage electrical networks, it is necessary to analyze the operation of the lines relay protection in order to avoid cases of the existence of a dangerous voltage with a time exceeding the maximum allowable voltage on the grounding devices.

Keywords:neutral, grounding, relay protection, touch voltage, insulation, grounding device