Fire and explosion prevention measures for power transformers
power transformers are the main equipment for power transmission and distribution in the power system. The power transformer is mainly used to reduce the high voltage of electricity to 6000 volts (V) or 380 volts (V) that can directly make the gauge distance at the time of fracture more than 1 meter, so as to supply power to electrical equipment. If there is overload or short circuit inside the transformer, the insulating material or insulating oil will decompose, expand and gasify due to high temperature or electric spark, so that the internal pressure of the transformer will increase sharply, which may cause the explosion of the transformer shell, a large amount of insulating oil will spray out and burn, and the oil flow will further expand the fire risk
precautions against fire and explosion during operation:
strictly control the additional capacity of excess products (1) do not overload operation: long term overload operation will cause coil heating, gradual aging of insulation and short circuit
(2) regularly check the quality of insulating oil: the oil quality should be tested regularly, and unqualified oil should be replaced in time. At the same time, or take other measures with its oxygen index of 32 ~ 45
(3) prevent insulation aging damage of transformer iron core, and insulation aging caused by long-term heating of iron core
(4) prevent the insulation from being damaged due to careless maintenance. If it is found that it is damaged, it should be handled in time
(5) ensure that the wires are in good contact, and local overheating will occur due to poor contact
(6) prevent lightning strike, and the transformer will be burned due to insulation breakdown
(7) short circuit protection: if the transformer coil or load is short circuited, the transformer may be burned out if the protection system fails or the protection setting is too large. To do this, install reliable short-circuit protection
(8) well protected grounding
(9) ventilation and cooling: if the transformer coil wire is class a insulation, its insulator is mainly paper and cotton yarn. For every 8 ℃ rise in temperature, the insulation life will be reduced by about half; The normal temperature of the transformer is below 90 ℃, and the service life is about 20 years; If the temperature rises to 105 ℃, the service life is 7 years. Keep good ventilation and cooling during transformer operation
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