Abstract: The test of extinguishing the oil pool fire of the converter transformer was carried out by building an experimental platform independently, the data of the mist flow density, temperature, heat flow, and thermal imaging collected in the experiment was analyzed. The fire extinguishing characteristics of the water spray and foam spray system was obtained, and the difference of fire extinguishing efficiency of these two fire extinguishing systems was obtained too. The results showed that the fire extinguishing time of water spray and foam spray were 190 and 100 s, the final heat flow value of the water spray fire extinguishing system and the foam spray fire extinguishing system reduced to 0.005 9 and 0.004 7 W /m2. Compared with water spray fire extinguishment, heat decreases rapidly when foam spray putting out the fire, and the fire extinguishing time is short. The fire source can be effectively controlled within 100 s. Under the same basic conditions, the efficiency of foam spray fire extinguishment is higher than that of water spray fire extinguishment.

Key words: transformer oil pool fire, water spray fire extinguishing system, foam spray fire extinguishing system, fire extinguishing efficiency