The electromagnetic transient interference caused by the switch operation of the circuit breaker inside the switchgear will be transmitted to the secondary control and intelligent equipment through the electronic instrument transformer（EIT） which is a great test to the insulation capability of the sensor and the secondary equipment.And the effect may bring the measurement error.In this paper through the circuit analysis and electromagnetic transient simulation the circuit model of the electronic voltage transformer（EVT） in the 10 kV switchgear is established and the transient response of the disconnector under the no-load busbar is analyzed.It is found that the transient response output amplitude of EVT is up to several times of the fundamental-frequency value the high frequency interference are upper megahertz the high frequency interference bands is mainly distributed at 200 kHz 1.25 MHz and1.7 MHz.Compared with the electromagnetic transformers it is found that the transient characteristics of ETs and ElTs are quite different.The experimental scheme based on electromagnetic transformer（ET） for the transient performance of EITs needs to be improved.The simulation results provide theoretical analysis for the actual operation of the EVTs which can improve the electromagnetic protection performance of the EVTs and its long-term operational stability.