Abstract: This article combines the 220 kV system of the 500 kV substation in the main grid of Inner Mongolia Grid to explore the busbar structure and common dead zone faults of the 220 kV system. It relies on bus differential protection and failure protection to eliminate the faults. The analysis focuses on the need to charge the equipment before operation due to infrastructure, production, and other projects. This article discusses the characteristics of two charging methods, and proposes that for the charging of new equipment, the charging method based on the protection device's logic of charging to the dead zone should be selected to reduce the scope of removal, avoid potential hazards, and ensure the stable and reliable operation of the power grid.