Performance comparison of glass and composite insulators
- 發(fā)布時(shí)間：
- 2019-03-15 10:50:00
摘要：Performance Comparison of Electric Porcelain, Glass and Composite InsulatorsA variety of atoms in the bulk of Elec
Performance Comparison of Electric Porcelain, Glass and Composite Insulators
A variety of atoms in the bulk of Electroceramics or glass materials are combined by ionic bonds through electrostatic attraction, so the stability of Electroceramics and glass is very good. High-pressure wall-piercing bushing also means that the surface energy and thermal momentum of the two materials are high, so the surface of the material has a strong ability to absorb water. In other words, the ceramic or glass surfaces of HV disconnectors are more susceptible to moisture. For electric ceramic or glass insulators, in order to make insulators have higher surface resistance in wet and dirty environment, it is necessary to make high voltage insulators have larger leakage distance and more complex structure shape. Electric ceramics and glass are very dense materials with a large proportion. Therefore, electric ceramics and glass insulators are very bulky. The compressive strength of these two materials is higher than the tensile strength. But these two materials are brittle materials. Care should be taken in transportation and installation to avoid breakage. The advantage of composite insulators is that umbrella sheath materials of composite insulators are made of organic materials. Compared with inorganic materials such as electric ceramics or glass, the elements of organic materials are combined by covalent bonds. The bonds and forces between the elements are relatively weak. The macromolecules of organic materials are easy to break, so they are discharged in corona. Under the action of ultraviolet radiation, moisture, temperature change and chemical factors, organic insulating materials are easy to aging. The electrical and mechanical properties of composite insulators will gradually decline with the running time, and this performance decline is irreversible.
If the deterioration of a material's performance is recoverable, the high-voltage insulator is called fatigue; if the deterioration of the material's performance is not recoverable, it is called ageing. All high voltage insulator materials have aging problems, but the aging speed of different materials is very different. Although electrical porcelain and glass also have aging problems, but because the aging rate is very low, it does not become a serious problem in operation, so the aging problem of electrical porcelain or glass insulators is seldom discussed. Under the action of voltage and external factors, aging of composite insulators is a serious problem. Therefore, in the discussion of the use of composite insulators, aging is often a topic to be mentioned.