EP7

Understanding of transformer bobbin:

Bobbin (skeleton) plays the role of supporting coil (coil) in the transformer.

According to the different nature requirements of the transformer, it can be divided into thermoplastic materials and thermosetting materials.

Thermoplastic materials we commonly use are nylon, plastic and plastic. Thermosetting materials we commonly use are bakelite.

Characteristics and uses:

1. Bakelite (PM): thermosetting material with high stability, not easy to deform, temperature resistance of 150 ℃, high temperature of 370 ℃. The surface is smooth, fragile and can not be recycled. It is used for transformers with high temperature resistance.

2. Nylon: thermoplastic material, engineering plastic, with good ductility, not fragile, temperature resistance of 115 ℃, easy to absorb water, baked at 80 ℃ before use to make it stable. The surface is smooth, translucent and not fragile. It is generally used in transformers with strong oil resistance.

3. Plastic (PET): thermoplastic material, high hardness, easy to form, not easy to deform, temperature resistant to 170 ℃, non smooth surface, not fragile, generally used for bobbin.

4. Plastic (PBT): thermoplastic material, soft, not easy to deform, not resistant to high temperature (160 ℃), not smooth and not fragile, generally used for bobbin.

Material selection:

Conventional high-frequency transformer bobbin mainly uses bakelite powder materials as basic materials, such as t373j and t375j materials of Changchun company, pm9820, pm9630 and LCP materials of Sumitomo company. The material is brittle and fragile, and the fire rating is 94V-0. It can withstand high temperature (370 degrees), voltage resistance is about 10kV / mm, and the surface is smooth. It can be said that bakelite is the most used material in transformers, because it has high temperature resistance, no deformation, medium voltage resistance and is suitable for large and medium-sized power transformers.

Another kind of PET material is often used for bobbin support of high-frequency transformer wire rack. PET: chemical name polyethylene terephthalate, abbreviated as pet, is the most important variety of thermoplastic polyester, commonly known as polyester resin. Pet is easy to melt and form when heated. Its temperature resistance is around 130 degrees. It is not easy to deform after heating (thermal deformation temperature is 246 degrees). Its fire rating is 94V-0 and voltage resistance is 18kV / mm. It can be used as bobbin of high-frequency transformer and inductor shell. Its price is slightly higher than that of PBT.

Bobbin, a high-frequency transformer framework, can be selected and customized according to customers' specific use scenarios and requirements.