Fire prevention measures caused by power transformer failure

The cause of the fault is due to severe overload operation, short circuit of coil insulation damage, aging of transformer oil, excessive contact resistance at the joint or tap, high and low voltage fuses failing when the external line is shorted, core damage and arc flash in the oil. Caused by network, lightning strikes and other reasons. Since the inside of the transformer is filled with insulating oil, the consequences are very serious in the event of fire. If the oil is injected, the internal pressure of the transformer will rise sharply due to the decomposition and gasification of the oil, causing the shell to burst and a large amount of oil to burn. The preventive measures are:

(1) The power transformer should be equipped with a fuse or relay protection device. When the capacity is large, a gas relay should be attached to cut off the faulty transformer and the power grid in time.

(2) Strengthen insulation monitoring, and conduct preventive tests and rotation maintenance of transformer insulation on a regular basis.

(3) Do a good job in the management of insulating oil. If oil aging, water ingress, and insufficient insulation strength are found, oil filter treatment or replacement of qualified new oil should be carried out.

(4) The transformer shall be installed in an outdoor or first or second class fire rated building and shall be well ventilated.

(5) Strengthen operation management, often monitor the load of the transformer during the peak load time. If the overload is found, the load transfer should be taken or replaced with a larger capacity transformer.

(6) Regularly check whether the arrester is working normally, and replace the unqualified products in time.

(7) Promote the application of fully sealed power transformers. For high-rise buildings and places of particular importance, dry-type transformers or box-type substations with flame retardant or self-extinguishing properties should be used.