Transformer failure situation When the staff on duty at the transformer substation finds an abnormal phenomenon in the operation of the transformer, they should try to eliminate it as soon as possible, and immediately report to the superior and make a record. When a serious fault of the transformer is found, the transformer should be shut down without reporting to the dispatcher. If there is a spare transformer in operation, put it into operation as soon as possible, and then report to the dispatch and leadership. Such as: 1. The sound of the transformer is obviously increased, which is very abnormal, and there is a popping sound inside. 2. Severe oil leakage or fuel injection causes the oil level to drop below the design limit of the oil level. 3. The casing has serious damage and discharge. 4. The transformer is smoking and catching fire. Troubleshooting of the transformer 1. The sound of the transformer is obviously increased, which is very abnormal, and there is a popping sound inside. 1. Check the load of the transformer and the temperature of the cooling medium, and compare it with the same load and cooling conditions in the past; 2. Check the temperature measuring device; 3. Check whether the radiator valve is open, and whether the cooling device or transformer room ventilation is normal. If all the above are normal and the oil temperature is 10°C higher than the previous under the same conditions, and it continues to rise, it can be concluded that there is a fault in the transformer, such as iron core fire or inter-turn short circuit. The fire of the iron core may be caused by eddy current, or the clamping screw is in contact with the iron core, or the insulation of the silicon steel sheet is damaged. At this time, the gas protection of the differential protection does not operate. The gradual development of iron core ignition causes the oil color to gradually darken, and because the temperature of the ignition part rises quickly, the temperature of the oil gradually rises and reaches the ignition point temperature. This is very dangerous. If the transformer is not removed in time, it may be possible A fire or explosion accident occurred. Therefore, it should be reported to the superior immediately, and the transformer should be shut down and repaired. 2. The main transformer leaks oil and catches fire. When a large amount of oil leaks from the transformer and the oil level drops rapidly, it is forbidden to change the heavy gas protection to only act on the signal. Because the oil level is too low (lower than the top cover), there is no heavy gas protection action to trip, which will damage the lead insulation. Sometimes there is a "sizzle" discharge sound inside the transformer, and an air layer is formed under the transformer top cover, which should be very dangerous, so measures must be taken quickly to prevent oil leakage. When the transformer catches fire, the power supply should be cut off immediately and the cooler should be stopped. If the upper part of the top cover catches fire, if the transformer is equipped with an accident drain valve far away from the body, immediately open the accident drain valve and put the oil in the drain tank lower than the fire place. At the same time, use a carbon dioxide fire extinguisher or sand to extinguish the fire. Pay attention to the direction of oil flow to prevent the expansion of fire and cause other equipment to catch fire. 3. The main transformer protection action. 1. Handling during gas protection action. According to the different nature of the accident, gas protection can be divided into two types of actions: one is to act on the signal without tripping; the other is that both occur simultaneously. The light gas protection action usually has the following reasons: a. Air enters the transformer due to oil filtering, refueling and activation of the strong oil circulation device; b. The oil level is slowly lowered due to temperature drop or oil leakage; c. Due to external penetration A small amount of gas is generated by short-circuit; d. Due to the influence of external short-circuit current; e. Misoperation caused by damage to the insulation of the DC circuit or deterioration of the contact. The cause of the tripping of heavy gas protection action may be due to a serious fault inside the transformer, a sharp drop in the oil level or a failure of the secondary circuit of the protection device; in some cases, if the oil and air separate too fast after maintenance, it may also cause The heavy gas protection acts on tripping. After the gas signal occurs, the sound signal should be stopped first, and the cause of the operation of the gas relay should be checked. If it is not caused by the above reasons, the gas in the Buchholz relay should be collected immediately, and the nature of the fault should be judged according to the amount, color, and flammability of the gas. If the gas in the gas relay is colorless, odorless, and non-flammable, and the chromatographic fan judges to be air, the transformer can continue to operate and eliminate the air intake defect in time. If the gas is combustible and the flash point of the oil is lower than the past by more than 5°C, it means that there is a fault inside the transformer, and it must be stopped for treatment, and reported to the superior in time, and it is strictly forbidden to send power rashly. 2. Processing when differential and quick-cutting protection action. When the main protection of the transformer (differential or quick cut) is acting on tripping, if there is a backup transformer, the backup transformer should be put in first, and then all parts within the protection range should be checked. a. Check whether the transformer bushing is intact and whether there are flashover traces on the bus bar connected to the transformer; b. Check whether the cable head is damaged and whether the cable is moving. If the inspection result does not find the above phenomenon, it should be found whether there is a fault inside the transformer. When there is operation inside the transformer, the transformer is not allowed to switch on and transmit power. Sometimes, when the differential protection is short-circuited outside its protection range, it may malfunction. If there is no sign of operation of the transformer, if it is possible, the transformer can be subjected to a step-up test from zero before sending power; if it is unconditional, the DC circuit of the differential protection should be checked. If the transformer is not found to be faulty, it can be switched on without load for a trial transmission; after the switch has been switched on, it can be connected to other lines only when it is normal. If everything is correct at the time of the trip, the protection device may have malfunctioned. At this time, the circuit breakers and isolating switches on each side should be disconnected, and the entire set of differential protection devices should be tested by the tester. If the differential protection action is correct, the fault must be found and eliminated before the transformer can be put into operation. If it is current quick-break protection, the handling of its action trip can refer to the handling of differential protection action