Method and device for switching power supply in electric power system

A method for power supply switching in an electric power system, the method comprising:

• providing an electric power system including two power supplies, each of the power supplies being connected to a bus through an incoming line, one of the power supplies currently supplying power being used as a main power supply, another of the power supplies being used as a backup power supply, and the two power supplies being respectively connected to a power supply station of a higher level;
• upon identifying a trigger condition, starting sampling of power data on the bus, and using the trigger condition to decide that a fault of the electric power system is eliminated and power is lost from the main power supply;
• and
• upon a time period for sampling of power data reaching a preset threshold, determining whether a condition for circuit-closing of the backup power supply is satisfied according to each sampled value of the power data.

A quick switching device located in an electric power system, the electric power system including two power supplies, each of the power supplies being connected to a bus through an incoming line, one of the power supplies currently supplying power being used as a main power supply, another of the power supplies being used as a backup power supply, and the two power supplies being respectively connected to a power supply station of a higher level,

• the quick switching device comprising:
• an acquisition unit configured to start sampling of power data on the bus upon a trigger condition being identified, the trigger condition being used to decide that a fault of the electric power system is eliminated and power is lost from the main power supply;
• and
• a determining unit configured to determine, upon a time period for sampling of power data reaching a preset threshold, whether a condition for circuit-closing of the backup power supply is satisfied according to each sampled value of the power data.