Analysis of the false grounding phenomenon in high-voltage distribution networks and countermeasures

With the continuous development of social economy at the same time the scale of the power grid has gradually grown, the $\mathbf{6 6 k V}$ high-voltage distribution network structure has become very complex, the stability of the high-voltage distribution network determines whether the power grid can provide users at all levels with safe, qualified and uninterrupted electric energy. However, the phenomenon of false grounding fault occurs frequently in the high-voltage distribution network, which brings many adverse effects on the stability of the power grid, and even in extreme cases, false grounding fault may cause the insulation breakdown of the power grid equipment, leading to large-scale power outage or power grid collapse. This paper analyzes the phenomenon and causes of false grounding fault in 66 kV north bus system of KJG 220 kV substation, and eliminates the false grounding fault in high voltage distribution network by using the calculation method of neutral unbalance degree of power system and reducing the neutral displacement voltage.