With the fast development of power system

intelligent equipment is increasingly applied in substations. Disconnector operation in gas insulated switchgear（GIS） always produces electromagnetic field emissions. Therefore

it has very important reference significance to analyze the electromagnetic field distribution for the electromagnetic compatibility design of the electronic equipment installed around the GIS enclosures. We established the circuit models of grounding enclosure and electromagnetic emission

and calculated the electromagnetic field caused by the enclosure current during switching operation. The results show that the electromagnetic field waveform follows the enclosure current waveform. Near the enclosure

the electromagnetic field decays fast

far from the enclosure

electric field decays linearly while magnetic field decays exponentially. With the number increasing of grounding points

the amplitude of TEV decreases obviously

and the electromagnetic field are smaller far from the bushing. The electromagnetic field near grounding enclosure is measured

and the measured results basically coincide with the calculation results.