Abstract: In order to improve the fire protection capacity of the main transformer of 330 kV substation and ensure the safety of the power grid, the paper analyzes the current situation and shortcomings of the fire protection facilities configuration of the main transformer of 330 kV substation, compares the advantages and disadvantages of four main transformer fire protection capacity improvement schemes, namely, fixed foam spray fire extinguishing system, compressed air foam fire extinguishing system, foam water mist vortex fan fire extinguishing system, and robot fire extinguishing system, determines that the robot fire extinguishing system is more suitable for the fire protection capacity improvement of the main transformer of 330 kV substation, and proposes an intelligent foam spray vortex fan robot fire extinguishing system. The test shows that the intelligent foam spray turbofan monitor robot extinguishing system puts out the oil pool fire in 6 minutes, the transformer and radiator top surface fire in 6.7 minutes, the casing spray fire in 7.2 minutes, successfully controls the fire, and extinguishes all open fires in 9.5 minutes without reburning. A typical fire extinguishing system scheme for the main transformer of a 330 kV substation has been designed, providing reference for the subsequent improvement and renovation projects of the fire protection capabilities of the main transformers in 330 kV and 500 kV substations, as well as the design of the fire extinguishing system for new substations.

Key words: 330 kV substation, improving scheme for fire protection capability, fire robots, fire extinguishing system