Do dry-type epoxy resin transformers need to be dried?

Dry-type epoxy resin transformer is an important electrical equipment, and it is also necessary to pay attention to various operations in the process of operation, among which the drying of dry-type epoxy resin transformer is more common. Because the dry-type transformer will sometimes enter the water or get wet when it is working, in order to prevent short-circuit, the dry-type transformer is dried. Whether the dry-type transformer needs to be dried depends on the following situations.

(1) For the newly installed dry-type epoxy resin transformer with oil transportation, whether it needs to be dried, the following conditions should be comprehensively analyzed.

1) The electrical strength of insulating oil and trace water test are qualified

2) Insulation resistance and absorption ratio (or polarization index)

3) The dielectric loss tangent value tanδ (%) is in line with the regulations (the voltage level is below 35kV and the capacity is below 4000kV.A, it is not required).

(2) For newly installed dry-type epoxy resin transformers and reactors for inflatable transportation, the following conditions should be comprehensively analyzed to determine whether drying is required:

1) The pressure inside the body is kept positive from the factory to the installation;

2) The trace water in the residual oil should not be greater than 30ppm;

3) After the dry-type transformer and reactor are injected with qualified insulating oil, the electrical strength of the insulating oil and the trace amount of water and the insulation resistance should meet the current national standards.

(3) When the body fails to maintain positive pressure and the seal is not damaged obviously, a comprehensive judgment should be made based on a comprehensive analysis of the installation and test records to determine whether drying is required.

Dry-type transformers do not mean that they must be dried. It is necessary to see if there is any need for drying. For dry-type transformers, the drying process should be improved, so that dry-type epoxy resin transformers can run safely and smoothly, and achieve continuous efficiency. to improve.