Polymer insulators are a type of insulator used both in transmission and distribution power lines and substations. Polymeric insulators have their main advantage in mechanical resistance against shocks due to the flexibility and behavior of the insulator derived from using the polymeric material.
Firstly, composite insulator excels in mechanical properties. Its core rod is usually made of epoxy glass fiber, with an expansion strength 1.5 times that of ordinary steel and 3 to 4 times that of high-strength porcelain. At the same time, it also has strong vibration absorption capacity and high seismic damping performance, which is 1/7 to 1/10 of that of porcelain insulators. This enables the composite insulator to withstand significant mechanical loads and vibrations, ensuring the stable operation of the power system.
Secondly, the composite insulator has excellent anti-pollution flashover performance. Its surface is hydrophobic, and when it rains, the rainwater does not form a water film on its surface but instead falls in droplets, which makes it less likely to form a conductive channel. This allows the composite insulator to maintain high insulation performance even in harsh environments, reducing flashover accidents caused by pollution.
Furthermore, the composite insulator exhibits superior electrical erosion resistance. The standard for irreversible degradation and tracking caused by surface leakage flashover is typically no less than grade 4.5 (i.e., 4.5kV), while the composite insulator can reach grades 6 to 7, significantly improving the insulation level of the power system.
