Abstract: This paper analyzes the cause of fire of oil-immersed transformer in multi-station fusion substation and develops a set of intelligent fire-fighting device for oil-immersed transformer in substation. The device uses LoRa wireless communication technology to remotely monitor the temperature, flame and smoke status of oil-immersed transformer, and uses multi-stage fire warning algorithm to judge and identify the fire situation, so as to improve the ability of early detection, early warning and timely extinguishing of the fire to ensure the safe and stable operation of oil-immersed transformer.The device was tested in transformer fire simulation field. The test results show that the device has sensitive communication and can extinguish the fire timely .

Key words: fire protection, multiple station fusion, oil-immersed transformers, intelligent fire extinguishing installation