Abstract:The mechanical properties of composite electrical equipment are better than ceramic electrical equipment and it have broad application prospects in substation or converter station. In order to research the seismic response of ±800 kV composite pillar insulator, enhance the seismic level of composite electrical equipment, ±800 kV converter station composite material pillar insulator connected circuit was taken as an object, then the seismic response law of composite electrical equipment under seismic actionwas researched, the influence of the conductor stiffness and equipment stiffness on the seismic performance of the connected equipmentwere analyzed by using structural dynamics theoretical analysis method and establishing two degrees of freedom theoretical model and dynamic equation of interconnected electrical equipment. The results showed that as the stiffness of the connecting wire increases, the displacement of the high-frequency equipment is slightly larger than that of the low-frequency equipment. The greater the difference in wire stiffness, the greater the difference in seismic response between the two equipment. Under the premise of electrical function, increasing the redundancy of the wire is beneficial to improve the seismic performance of the equipment. In order to reduce the seismic response of the connected equipment, the two equipment with close frequency are interconnected as much as possible to reduce the seismic coupling effect between the equipment. Then the principle of the frequency matching and the conductor design between the composite electrical equipment were put forward, which provided reference for the seismic design of the equipment.