Common problems and solutions in transformer high voltage testing

In the high-voltage test of transformers, many key points should be paid attention to, and the test conditions and test methods must be accurately grasped. The faults that occur in the transformer high-voltage test should be screened one by one, and the faults should be properly handled. Ensure that the transformer does not have any hidden fault hazards, and then put into use in the power grid. In this paper, the conditions and methods of transformer high voltage test are discussed, and the treatment methods of different faults are analyzed.

       1.Abnormal sound inside the transformer and solution.

If the transformer is in normal working condition, it produces a stable electromagnetic AC sound frequency, so there will be no abnormal sound inside the device. If in the process of high voltage test, there is an abnormal noise inside the transformer, indicating that the transformer is not in good working condition, which may be due to excessive load, failure of internal parts of the transformer, excessive internal bearing voltage of the transformer, or poor contact, these reasons will make the transformer make abnormal noise. At this time, the tester should quickly stop the test, cut off the power supply, diagnose the cause of the sound, do careful inspection work, solve the fault that caused the abnormal noise, and then carry out the test.

    2.Automatic tripping problem of transformer and solution.

In the process of transformer high voltage test, sometimes there will be tripping phenomenon, at this time the test personnel should carefully check the transformer to find the cause of the failure. If the trip is only caused by a problem with the operation of personnel, then there is no need to inspect the transformer. If the tripping caused by human operation error is excluded, then the tester must conduct a thorough inspection of the transformer, the internal and external structures can not be let go, and all kinds of hidden dangers are checked one by one to avoid safety accidents and losses in the later test process. Once a fire occurs in and around the transformer, the power transformer will react quickly, cut off the power supply, and turn on self-protection. If the transformer fails to activate the protection mechanism for some reason when the fire occurs, the staff needs to manually cut off the circuit breaker and extinguish the fire.

3.Transformer oil level problem and solution.

In general, the oil level of the transformer needs to be controlled to be within the allowable range, and the oil level of the transformer can be adjusted according to the specific operating conditions. Therefore, in the process of high-voltage testing, if the oil level changes greatly, it is necessary to check the transformer at this time to see if it is caused by oil leakage, if the rise of the oil level is very obvious, the first thing to consider is whether it is affected by the temperature, if it is determined that the temperature is in the normal range, then the operator needs to check the equipment, check each related component, and determine and deal with the fault.

4.Transformer gas protection and solutions.

Through the analysis of the test, it can be concluded that when the transformer is carried out in the high voltage test, there are many reasons for gas protection failure, among which the most common reasons are the failure inside the transformer, the failure in the protection device, and the oil level of the transformer drops faster than the normal range. Therefore, for so many situations that are easy to cause failure, transformer high-voltage testers need to carefully inspect the equipment, eliminate all causes of gas failure, ensure the smooth progress of transformer high-voltage testing, and ensure its future use safety.

5.Winding faults of transformer and solutions.

Winding failure is also a problem at a higher frequency in the transformer high voltage test, based on this, the inspection of the power transformer should be carefully completed before the start of the test, according to the steps to check one by one, the reasons for the winding failure are multiple, see short circuit, inter-turn section road, etc. will cause winding failure, for these more careful inspection to eliminate, to ensure that the transformer can operate safely and stably after use, so that the transformer can better serve us.