Discussion on light gas action treatment of the ho

Discussion on the treatment of transformer light gas action

during the operation of the transformer, after the light gas protection signal acts, the causes should be found out as soon as possible, and records should be made, the transformer should be checked externally and analyzed for gas, and then corresponding treatment measures should be taken according to the inspection results

external inspection of transformer: check the indication of ammeter and voltmeter, insulation of DC system, and whether there are other protection action signals. Check whether the oil color and oil level of the transformer are normal and whether the upper oil temperature rises significantly. Check whether the sound of transformer is abnormal. Check the oil conservator and explosion-proof pipe of the transformer for oil injection and emission, and the packing and plug gasket for deformation. Check whether there is gas in the gas relay. If there is, take gas for inspection and analysis. If nothing else is abnormal, and the gas relay is full of transformer oil, but there is no bubble rising, it is a malfunction

if there is no obvious abnormality in the above external inspection, the gas should be taken immediately for analysis. The gas should be taken after the power failure. If there is serious abnormality in the inspection, the dispatcher should be reported, the standby power supply or standby transformer should be put into operation, and the faulty transformer should be exited. The transformer that has not been inspected and processed and passed the test should not be put into operation

take the gas to analyze and determine that the gas released or the air entered during the internal slight fault of the transformer accumulates in the gas relay until the light gas relay acts and sends a signal. When taking gas, after observing and recording the volume of gas in the gas relay, open the vent valve to take gas, and then identify the color and flammability of the gas. The identification of the color and flammability of the gas should be carried out quickly to prevent colored substances from settling and disappearing after a certain period of time. The gas is analyzed and judged as follows:

the gas is colorless, tasteless, nonflammable, and belongs to the air entering the transformer. It may be because the air enters the transformer after new installation or maintenance, refueling and other work, and is not completely discharged after work. It may also be that the cooling during operation and the sealing of the submersible pump are not tight enough to enter the air. According to the different load measurement methods, the gas taken is colored, nonflammable, and cannot be determined as air. Oil samples should be taken and sent to professionals for testing. If the content of carbon monoxide is found to increase, it may be a gas decomposed due to overheating damage of solid (intrinsic) insulation

the gas taken is colored, odorous and combustible, which is an internal slight fault and should be powered off for maintenance. When checking whether the gas is combustible, keep away from the transformer. According to the inspection results, no abnormalities and faults were found in the external inspection of the transformer. The gas relay is full of oil, but there is no gas, which may belong to misoperation. At this time, check the interior and contact position of the gas relay, the insulation of the DC system and whether the gas signal can be reset if the contact of the gas relay is in the open position, and the gas signal cannot be reset if the card is dropped. It is due to poor insulation of the DC system, which may be caused by DC multi-point grounding; The gas relay contact is in the open position, and the gas signal cannot be reset when the card is dropped. The insulation of the DC system is normal, which may be caused by the misoperation caused by the short circuit of the secondary circuit. The short circuit point should be found out and eliminated; The contact of the gas relay is in the open position, and the gas signal can be recovered when the card is dropped. At the same time, various experimental data processing software and experimental accessories can be customized according to the domestic and international standards provided by the user. Check that the insulation of the DC system is good, which may be caused by the misoperation of light gas caused by excessive vibration, and identify the cause of the fault point and eliminate it. If it is checked that the gas relay is in the closed position, and the gas signal cannot be reset after losing the card, check the DC system. Let's take a look at the operating procedures and performance characteristics of the electronic universal testing machine. The insulation is good, which may be the problem of the gas relay itself (such as the fault of float oil inlet). In this case, the power should be cut off for treatment

check the transformer. It is found that there is no oil in the transformer conservator, the oil level is lower than the gas relay, and there are no other abnormalities. The light gas gives a signal, which may be caused by the gas action due to the low oil level. At this time, put the standby transformer or standby power supply into operation, exit the faulty transformer, if there is oil leakage, deal with the oil leakage, and then add oil to the required oil level

no obvious abnormalities and faults were found, and gas was found in the gas relay. Take the gas for inspection and analysis. If the gas is colorless, tasteless, and nonflammable, it may be the time interval of entering the air, releasing the gas, and monitoring the signal reporting. If the signal action time interval is gradually short, it indicates that there is a fault in the transformer, and it may trip. At this time, make a detailed record of each signal action time, and immediately report to the relevant dispatcher and superior leaders. If the gas relay enters the air, The reason and point of air inlet shall be found. If there is no standby transformer, the heavy gas can be switched to the signal position according to the dispatching order. If the gas is light and nonflammable, and it cannot be determined that it is air, report to the dispatcher and the superior supervisor, and closely monitor the transformer. Take oil samples and send them to professionals for testing. If there is a problem, power off immediately for maintenance. If the gas is colored, smelly and combustible, it may be a slight internal fault of the transformer. At this time, the standby transformer and standby power supply should be put into operation, and the faulty transformer should be powered off for maintenance

if abnormal and obvious faults are found in the transformer, input the standby transformer or standby power supply, exit the faulty transformer, and take gas for inspection, analysis and judgment