Insulation materials include gas insulation materials, liquid insulation materials, and solid insulation materials.
1. Gas insulation materials
Normally, dry gases under normal temperature and pressure have good insulation performance. As an insulating material, gas dielectrics also need to meet the requirements of physical, chemical properties, and economic efficiency. Air and Sulfur hexafluoride gas are commonly used gas insulation materials.
2. Liquid insulation material
Insulating oil includes natural mineral oil, natural vegetable oil, and synthetic oil, as shown in Figure 1. Natural mineral oil is widely used as a neutral liquid obtained by refining petroleum crude oil to varying degrees. It is golden in color and has good chemical stability.
3. Solid insulation material
There are many types of solid insulation materials, which have excellent insulation performance and are widely used in power systems. Commonly used solid insulation materials include: insulating paint and adhesive; Fiber products; Rubber, plastics and their products; Glass and ceramic products; Mica, asbestos and their products.
The above is an introduction to the classification of insulation materials. Next, let's talk about extended materials:
Insulating materials are mainly used to isolate live parts with different potentials in electrical equipment, so insulating materials should first have high insulation resistance and withstand voltage strength, and can avoid leakage, breakdown and other accidents.
The higher the voltage applied at both ends of the insulator, the greater the electric field force on the charges inside the material, making it more prone to ionization collisions and causing insulator breakdown.
The lowest voltage that causes an insulator to break down is called the breakdown voltage of this insulator.
When a 1mm thick insulating material is broken down.
The number of kilovolts that need to be applied is called the insulation withstand voltage strength of the insulation material, abbreviated as insulation strength.
Due to the certain insulation strength of insulation materials, various electrical equipment, safety tools (such as electrician pliers, test pens, insulation gloves, insulation rods, etc.), various electrical materials, and manufacturers have specified a certain allowable voltage, which is called the rated voltage. The voltage withstood during use should not exceed its rated voltage value to avoid accidents.
