Why Perform DGA in Oil Filled Electrical Equipment

Why Dissolved Gas Analysis is required for oil filled electrical equipment ? Because if some potential problems happened inside the transformers and electrical equipment, accompanied by gas generated, and these gases dissolved in the oil. So by analyzing the dissolved gas, user can predict the problems happened in the electrical equipment.

As a means of insulation supervision, in the past, DC leakage, insulation resistance, dielectric loss measurement, AC withstand voltage test, partial discharge measurement and other insulation characteristic tests were commonly used. However, the disadvantage of these tests is that the equipment under test is required to be temporarily shut down, the insulation cannot be continuously monitored, and it is difficult to detect very small internal faults before the accident occurs. Among them, the partial discharge test is a better method to detect the partial defect of insulation, but under the condition of the existing instrument, it is often affected by external interference, especially the transformer, which affects the accuracy of its detection.

 

The use of gas chromatography to analyze the dissolved gas in the oil of oil-filled equipment is an effective preventive test method for detecting latent faults such as overheating and discharge of oil-filled equipment such as transformers. The analysis can judge the hidden dangers in the operation of the equipment, the nature and severity of the latent faults, etc., can make early predictions, prevent accidents before they happen, and ensure the safe operation of oil-filled electrical equipment is of special significance. The actual developing faults can be repaired in a planned and economical way, thereby avoiding equipment damage and unplanned power outages. It can change the principle of "required repairs when due (required at regular intervals), and must be repaired well" to "required repairs, and must be repaired well", which is also a contribution to economic operation.

 

It can identify the correlation between equipment defects and operating conditions, so as to ensure normal operating conditions for safe operation, such as load, temperature rise, etc., so as to avoid overheating damage to equipment.

 

It can help analyze the cause of the action of the gas relay, so as to guide the elimination of the cause of the action of the gas relay.

 

For the equipment that has occurred accident, it is helpful to know the nature and damage degree of the equipment accident immediately, so as to guide the maintenance.

 

It can help ensure that new equipment is not damaged.

 

However, chromatographic analysis cannot predict accidents such as suddenness and insulation breakdown, so gas analysis must be comprehensively analyzed with other chemical and electrical test results to ensure safe power generation. Therefore, although the analysis of gas in oil is important, other test methods cannot be ignored.

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If interested in more details of Dissolved Gas Analysis Tester, please feel free to contact us.

PureTech Oil Filtration

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Tel:+8617815389416

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