Different method to Analyze to Combustible Gases in DGA Transformer oil Testing

Different method to Analyze to Combustible Gases in DGA Transformer oil Testing

There are a number of method to predict the Dissolved Gas Analysis in the transformer which is filled with beta fluid. The following processor that are recommended by dielectric system

Evaluation of Transformer Condition Using Individual and TDCG Concentrations:

These methods are suggest by IEEE Standard C57.104.when we have not the previous Dissolved gas history then a four level processes is define to understand the risk of inside the transformer. In the given table the concentration of gases are defined.

Condition 1

Total dissolved combustion gas show the transformer operate satisfactory manner if the TDCG below the level. If we find the concentration of gas increase for the given value then we should investigate the reason and try to find the fault.

Condition 2

In this stage it show that the combustible gas concentration is greater than the normal TDCG indicate and we should investigate the any single one gas increasing concentration for the specified level.

Condition 3

In this stage the TDCG indicate the level of decomposition is high. Any one gas which one increase its concentration level we should explore immediately if we doing this we easily recognized the fault present in the transformer. 

Condition 4

At this last condition these values indicate the proper transformer condition .TDCG indicate that the decomposition of beta fluid and the cellulose is uncontrolled. If we star doing work with transformer then the maximum chance that the transformer stop doing work due to out of order.

At this last condition these values indicate the proper transformer condition .TDCG indicate that the decomposition of beta fluid and the cellulose is uncontrolled. If we star doing work with transformer then the maximum chance that the transformer stop doing work due to out of order.

We can easily find the present condition of particular transformer by finding highest for a single one gas. A year old transformer as well as contain the level of gases that would be below the condition 1 and not enough acetylene is present in the transformer to detect. 

Evaluation of Possible Faults by the Key Gas Method

There are four type of faults which is presented in the key gases and cause to produce the problems. Key Gas Method not as precise but it is use widely in the investigation of faults in the transformer. Key Gas method is use to in beta fluid for the investigation of transformer conventional oil.

Fault Type: Thermal decomposition of Beta Fluid

Principal Gas: Ethylene Characteristics:

Ethylene and methane are produced from decomposition and along with small amount of hydrogen and ethane.

Fault Type: Thermal decomposition of Cellulose

Principal Gas: Carbon Monoxide Characteristics:

Carbon mono oxide and carbon di oxide is produced for the decomposition of cellulose. Hydrocarbon oxide are also produced if the cellulose saturated with beta fluid.

 Fault Type: Corona –partial discharge:

Principal Gas: Hydrogen Characteristics:

Hydrogen and methane is also produced due to ejection of corona. Carbon di oxide and carbon mono oxide is include if the corona take place in cellulose.

 Fault Type: Arcing

Principal Gas: acetylene Characteristics:

Acetylene and Hydrogen produced a large amount from arcing and other gas carbon di oxide is also produced in cellulose if the any potential harm is involve and the carbon also exist in the oil.