Before, when I saw those towering transmission towers, on one hand, I couldn't help but feel happy about these power equipment, and on the other hand, I also had a question in my heart: With so many wires transmitting huge amounts of electricity day and night, how can we ensure that these high-voltage lines don't harm the people around us? This is closely related to a crucial equipment: insulators, which play a crucial insulation role in the wires. Today in this article, let's step into its world together.

The first question is: What is the function of insulators?

As the name suggests, there is the word "insulation" in the name of an insulator, so its main function must be insulation, used to suspend wires and insulate them from towers and the earth. Whether it is a high-voltage line, an ultra-high voltage line, or an ultra-high voltage line, insulators can be omitted on any voltage level of overhead lines.

Secondly, what material are insulators generally made of?

It can be roughly divided into three types: porcelain insulators, glass insulators, and composite insulators.

The earliest and most experienced one is porcelain insulator, which can be said to be an antique. It can be said that it plays an indispensable role in the development of the power industry, and its characteristic is that it does not have hydrophobicity, which is exactly the opposite of lotus leaves. Lotus leaves are water droplets that do not stay on them, while porcelain insulators do not have this characteristic. Because of this, the dirt on the surface of porcelain insulators can become damp and humid under humid weather conditions. In order to ensure the insulation level of insulators, power supply employees need to clean the accumulated dust and dirt on their surface to prevent the insulation strength of the external insulation surface from decreasing and causing pollution flashover accidents. The maintenance cycle is approximately 5 to 8 years.

Along with it comes glass insulators. As the name suggests, its material is glass, mainly tempered glass. Once it deteriorates, it will self destruct, and power supply employees can identify it with the naked eye. Therefore, based on this characteristic, glass insulators do not need to undergo degradation detection. In addition, like porcelain insulators, it also has no hydrophobicity and needs to be cleaned to restore its surface insulation level.

Finally, composite insulators will be introduced. It is mainly made of silicone rubber and core rod materials. Unlike the above two types of insulators, its characteristic is to have hydrophobicity and migration of hydrophobicity. The surface of composite insulators cannot form a water film with certain conductivity, so their ability to resist pollution flashover is strong. Under normal operating conditions, composite insulators hardly require special maintenance, which can greatly save labor costs.

Finally, which transmission lines are insulators generally suitable for? Why are there more insulator strings for lines with the same voltage level in high-altitude areas?

According to different purposes, insulator strings are mainly divided into straight strings, jumper strings, and tension strings. The majority of tension insulator strings used in ultra-high voltage, ultra-high voltage lines, and DC lines are porcelain insulators and glass insulators; The majority of straight and jumper strings in dirty areas use composite insulators; In areas with relatively clean geographical environments, some use composite insulators, mainly porcelain insulators and glass insulators.

As for high-altitude or high-altitude areas, the number of insulator strings will be higher than transmission lines of the same voltage level in low altitude areas. In high-altitude areas, the electrical voltage of insulators with the same string length will decrease, and it is necessary to increase the length of the insulator string to improve the insulation level.