Effects of corona discharge on the properties of fiber reinforced plastics used in composite insulator

Fiber reinforced plastics (FRP) have been widely used as composite insulator inner rod material due to its excellent mechanical properties. In practice, composite insulator suffers from many kinds of environmental, electrical and mechanical stresses, such as discharge, pollution and liquids ingress. Under normal circumstances, the FRP rod is covered with the silicone rubber sheath, so there is no discharge happened on the surface of FRP rod. However, when the silicone rubber sheath is broken or the adhesion of the interface between the silicone rubber sheath and FRP rod is failed, some discharge will happen on the surface of FRP rod under operating voltage, which would lead to degradation and aging phenomena of FRP rod. In this research, the corona discharge is employed to simulate the discharge phenomena on the surface of FRP rod and investigate the influence of discharge on the properties of FRP rod.