Abstract: Abstract: The function of standby power supply is to quickly put the standby power supply into when the working power supply is disconnected due to a fault, so that the user will not affect the production and life because of a single line power supply, so as to improve the stability and reliability of the power supply system. This paper analyzes the types and principles, event history, event processing analysis and summary of substation self-investment, and provides some references for substation operators to deal with self-investment mistaken events.