How to Choose the Insulation Material of Transformer?

20Dec

How to Choose the Insulation Material of Transformer?

 

How to Choose the Insulation Material of Transformer?

1. Heat resistance
According to the insulation grade of the original design to choose the insulation material, can not use A insulation material to replace B insulation material, otherwise, will greatly shorten the service life of the transformer; On the contrary, if B class insulation material is used to replace A class insulation material, the material can not be fully utilized and caused waste.

2. Insulation performance
Pay attention to the insulation performance of materials. The insulation strength of low cable, capacitor paper and insulating board are different. Among them, capacitor paper is the best, and cable paper is the second.
If the provision of capacitive paper, can not be used to replace the thickness of cable paper; If it is stipulated to use two pieces of 1 mm thick cardboard, can not be replaced by a 2 mm thick cardboard.
Of the two terms, the former has higher insulation strength than the latter. The premise of material substitution is that the insulation strength must be the same.

3. Mechanical properties
Once the paper material loses its mechanical strength, it loses its insulation strength. Considering the mechanical strength, it is required that there should be no less than two pieces of insulating paper between layers, and two pieces of 1.5 mm thick cardboard should be used for rolling insulation cylinder.

4. Compression factor
The thickness of cardboard increases after moisture absorption, and decreases after drying. The deformation and shrinkage of cardboard should be considered when repairing transformers.

How to Choose the Insulation Material of Transformer?


1. Heat resistance

According to the insulation grade of the original design to choose the insulation material, can not use A insulation material to replace B insulation material, otherwise, will greatly shorten the service life of the transformer; On the contrary, if B class insulation material is used to replace A class insulation material, the material can not be fully utilized and caused waste.


2. Insulation performance

Pay attention to the insulation performance of materials. The insulation strength of low cable, capacitor paper and insulating board are different. Among them, capacitor paper is the best, and cable paper is the second.

If the provision of capacitive paper, can not be used to replace the thickness of cable paper; If it is stipulated to use two pieces of 1 mm thick cardboard, can not be replaced by a 2 mm thick cardboard.

Of the two terms, the former has higher insulation strength than the latter. The premise of material substitution is that the insulation strength must be the same.


3. Mechanical properties

Once the paper material loses its mechanical strength, it loses its insulation strength. Considering the mechanical strength, it is required that there should be no less than two pieces of insulating paper between layers, and two pieces of 1.5 mm thick cardboard should be used for rolling insulation cylinder.


4. Compression factor

The thickness of cardboard increases after moisture absorption, and decreases after drying. The deformation and shrinkage of cardboard should be considered when repairing transformers.