Abstract: Under 220 kV double-busbar connection mode, two busbars run in parallel through busbar interval. When the equipment of busbar interval is abnormal, it has great influence on double-busbar operation, the fault isolation mode directly affects the timeliness of fault treatment, the operation mode of lines and regional power grids on double-busbars, and improper treatment may cause all busbars to stop, or even the regional power grids to disintegrate, it directly threatens the safe and stable operation of equipment and power grid. This paper analyzes the advantages and disadvantages of three types of isolation treatment and restoration power transmission through an actual case of abnormal isolation and restoration power transmission of 220 kV busbar current transformer in a 500 kV ehv substation, it provides some reference for the treatment of this kind of fault.