Influence on Safe Operation in Active Distribution Network with Small Current Grounding Mode

When a large number of distributed generators access to the traditional distribution network, they will cause new risk problems on the safe operation of the power system. In order to analyse the impact of these problems, the simulation models of 10 kV distribution network, photovoltaic and wind turbine were established to explore the influence on safe operation in active distribution network (ADN) with small current grounding mode in this paper. The results show that, compared with neutral non-earthing mode, the neutral point grounding via the arc suppression coil can suppress the capacitive fault current, but increase the maximum value of earth potential rise of the earth connection grounding point. When the traditional power grid is connected with distributed generation, the fault voltage level of small current grounding mode is still within the safe range. If the safety of safe operation needs to be further enhanced technically, the low resistivity process of earth connection need to be improved.