According to the Code for seismic design of electrical installations （GB 50260—96） and the standard for high-voltage switchgear testing（GB/T 13540—92）in China as well as the related standard abroad（IEEE Std 693—2005）

seismic analysis and design of electrical equipment are discussed. Some of the key problems relating to seismic design of electrical equipment are put forward

such as seismic input in dynamic time-history analysis

dynamic magnification factor of equipment support

seismic fortification level

and so on. First

using ANSYS software

a finite element model of 220 kV SF6 ceramic cylindrical circuit breaker is established. Dynamic time-history analysis is carried out for three types of seismic input

and the dynamic time-history analysis method of the electrical equipment is introduced. The results about dynamic magnification factor of equipment supports

design of the supports

dynamic seismic input

and seismic capacity of equipment are obtained through analyzing such parameters as displacement

acceleration and stress of key nodes and positions on the circuit breaker. Secondly

by adjusting damping ratio of the circuit breaker’s bracket system

some effects of damping ratio on the response characteristics of the circuit breaker are obtained under three types of earthquake input. The seismic behavior of equipment can be significantly improved by increasing its damping ratio. This paper may benefit the revision of existing specifications and the constitution of related standards for seismic design of high-voltage electrical equipment in China.