Abstract: As the main power supply point within the county, the load transfer channel and capacity of the 220 kV substation after power loss are important factors affecting the reliability of power supply. This article focuses on the maximum degree of load transfer after 220 kV power loss, and studies the load transfer channel. Constrained by the transmission capacity of the transmission line and the power supply capacity of the substation during the load transfer process, it analyzes the load transfer situation and selects typical areas for analysis, which has a certain demonstration effect.