How many volts are the 27 insulators?
500kV transmission line. About 1 insulator is 6-10kV.
Insulator is a special insulation control that can play an important role in overhead transmission lines. In the early years, insulators were mostly used for telegraph poles, and slowly developed a lot of disk-shaped insulators hung on one end of the high-voltage wire connection tower. It was used to increase the creepage distance, usually made of glass or ceramic, called insulators. Insulators should not fail due to various electromechanical stresses caused by changes in the environment and electrical load conditions, otherwise the insulators will not have a significant effect and will damage the use and operating life of the entire line.
Insulator function:
There are many disc-shaped insulators hung on one end of the high-voltage wire connection tower, which is to increase the creepage distance, usually made of glass or ceramics, called insulators.
In order to prevent dust and other pollution from adhering to the surface of the insulator, the formation of a path is broken down by the voltage across the insulator, that is, creepage. Therefore, increase the surface distance, that is, the creepage distance, and the distance that discharges along the insulating surface, that is, the leakage distance is called the creepage distance. Climbing distance = Surface distance/Maximum voltage of the system. Depending on the degree of pollution, the creeping distance is generally 31 mm/kV in heavily polluted areas.
Zero value insulator refers to an insulator whose potential distribution at both ends of the insulator is close to zero or equal to zero during operation.
The influence of zero-value or low-value insulators: The insulation of line wires depends on the insulator string. Due to manufacturing defects or external effects, the insulation performance of the insulator will continue to deteriorate. When the insulation resistance is reduced or zero, it is called a low-value or zero-value insulator. We have tested the lines, and the proportion of zero-value or low-value insulators is as high as about 9%. This is another main reason for the high lightning trip rate of our company's lines. The insulator is smooth, which can reduce the capacitive reactance between the wires to reduce the loss of current.