The analysis of dissolved gases in transformer oil is one of the most important and commonly used technical means in the monitoring and fault diagnosis of power transformers. The principle is that when an electrical or thermal fault occurs inside the transformer, insulation oil and solid insulation materials will decompose under high temperature, arc or corona, producing various gases such as hydrogen, methane, ethane, ethylene, acetylene, carbon monoxide and carbon dioxide. These gases are partially dissolved in the oil, and by regularly or online detecting changes in the type and content of dissolved gases in the oil, it is possible to determine whether there are abnormalities and possible types of faults inside the transformer.

First,Analysis of Dissolved Gas in Transformer OilPlays a crucial role in early fault warning. Internal faults in transformers often do not have obvious external manifestations in the early stages, such as temperature, sound, and current changes, but the internal insulation has begun to deteriorate or partial discharge has occurred. At this point, potential issues can be identified by detecting small changes in the dissolved gas content. For example, the increase in hydrogen content is often related to partial discharge, while the appearance of acetylene often indicates the presence of internal arc discharge. These gases can be detected at an extremely early stage, which can buy valuable maintenance time for operators and prevent accidents from escalating.

Secondly, the analysis of dissolved gases in transformer oil has important value in determining the type of fault. Different types of faults correspond to different gas combinations and proportional characteristics. For example, low-temperature overheating mainly produces methane and ethane; Overheating at medium to high temperatures produces more ethylene; Severe arc discharge can produce acetylene. This provides a scientific basis for maintenance personnel to develop targeted handling measures.

Once again, the changes in the concentration of CO and CO ₂ in oil are of great significance for determining the degree of aging of solid insulation. Solid insulation releases a large amount of carbon monoxide and carbon dioxide during thermal decomposition. Therefore, when these two gases significantly rise, it often means that the insulation paper has undergone severe thermal aging or damage. The assessment of the remaining service life of transformers is crucial, which helps power companies to arrange equipment maintenance and replacement plans reasonably.

In addition, it is also applicable for long-term trend evaluation of transformer operation status. By regularly sampling and establishing a gas content change curve, the variation of gas generation rate can be observed. If the gas growth rate continues to accelerate, it indicates that internal faults are developing and require high attention; If the gas level remains stable, it indicates that the equipment is operating in a relatively healthy state. This trend analysis greatly improves the scientific and predictive nature of equipment management.

In summary, the analysis of dissolved gases in transformer oil plays an irreplaceable role in equipment fault diagnosis. It can not only achieve early warning and accurate judgment of fault types, but also evaluate the degree of insulation aging and predict equipment life, which is an important technical means to ensure the safe and stable operation of the power system. With the development of online monitoring technology and intelligent analysis technology, their applications will become more widespread, and their position in power equipment maintenance will be further enhanced.