1. What is the structure of the insulator? What does it do?
It should have sufficient insulation strength and mechanical strength, while having sufficient resistance to the erosion of chemical impurities, and can adapt to changes in the surrounding atmosphere, such as the impact of temperature and humidity changes on itself.
2. What is crawl distance? What is leakage ratio?
A: Creep distance and leakage distance are unique parameters of external insulation. The distance of discharge along the outer insulation surface is the leakage distance of electricity, also known as the creepage distance, referred to as the climbing distance. The leakage distance multiplied by the effective coefficient divided by the line voltage is the leakage distance, that is, λ=KL/U
Where λ is the leakage distance; K is the effective coefficient; L is the leakage distance; U is the line voltage.
3. What is flashover? What causes the pollution flashover?
A: When the gas or liquid dielectric around the solid insulation is broken down, the phenomenon of discharge along the solid insulation surface is called flashover.
There are many industrial dirty particles on the surface of porcelain insulators in dirty areas. When wet, these dirty particles will form a conductive liquid film on the surface of porcelain, which will significantly reduce the voltage resistance of porcelain insulation and make the flashover voltage very low. This is the reason why porcelain insulation is easy to flashover under dirty and wet conditions. Dirt and tide are the necessary conditions for dirt flashover, porcelain insulation only dirty and not wet will not cause flashover.
4. How to prevent insulator pollution flashover in substation?
A :(1) Increase basic insulation. Such as increasing the number of insulator pieces, increasing the discharge distance along the surface, to meet the leakage distance specified in the pollution classification.
(2) Strengthen cleaning. Porcelain insulation in dirty areas must be cleaned regularly to keep the surface of porcelain insulation clean and prevent pollution flashover. Live water flushing is an effective method.
(3) Use dust-proof paint. When the effective leakage ratio of porcelain insulation in dirty areas cannot meet the requirements and the cleaning workload needs to be reduced, silicone oil and floor wax are often used to increase the pollution lightning pressure and prevent pollution flashover accidents.
(4) Use semiconductor sleeve insulator and silicone rubber insulator.
