577 / 2017-05-14 22:45:51

Analysis and Verification of shed strength of 110kV Porcelain Post Insulator

Porcelain post insulator, shed strength, cantilever beam, porcelain brushing

Porcelain post insulators are widely used in power equipment as insulation-supporting structure. The current standard has clear requirements for the overall strength of porcelain post insulators; however, the operation and maintenance data of various operating conditions shows that shed damage is a major failure type of porcelain post insulators. At present, strength verification of cantilever beam is employed in the strength design of porcelain post insulator, focusing on the stress on the root of porcelain, with the strength of the shed and the stress between the sheds not taken into account. In this paper, calculation based on the main type of operation failure of 110kV porcelain post insulators shows that the stress between sheds near the root of porcelain brushing is much larger than the stress on the root of porcelain brushing, which is proved by experimental verification. According to the result, optimization of the current design and test criteria of porcelain post insulator is proposed.