In order to investigate the seismic performance of UHVDC composite post insulators and simplified calculation method for equipment interconnected by rigid bus

shaking table tests on a stand-alone composite post insulator and a interconnected system were carried out. The acceleration responses of key locations and root strain responses of post insulators were measured. Displacement responses at the top of post insulators were obtained by integral. The results show that the maximum root stress of the tested composite post insulators is lower than the allowable stress

and its behavior can satisfy the requirements of electrical equipment seismic response. All the peak acceleration amplification factor at the top of support

displacement responses at the top of post insulator

and root strains of insulators in an interconnected system

compared with those of a stand-alone composite post insulator

will decrease to an extent when subjected to the same input ground motion. The interaction between the rigid bus and post insulator can be simplified as linear spring

which constrains the seismic responses of equipment items. The seismic responses of equipment items in the interconnected system can be calculated and verified according to those of the stand-alone equipment when the equipment items are the same or of similar dynamic characteristics.