The 1 000 kV Jindongnan-Nanyang-Jingmen UHV AC test and demonstration transmission line project has been put into commercial operation.With the increase of voltage

the electromagnetic environment is more and more complicated

which may impose interference on the operation of radio station and the health of the residents and workers around the transmission lines.This paper calculated the electric field around the UHV AC transmission line making use of CDEGS software

and compared the output with the measured data.The result shows that the simulation output coincides with the measured data.According to the simulation output

the corridor width of the UHV AC transmission line is derived.In addition

two methods for suppressing the power-frequency distorted electric filed

i.e.setting shielded transmission lines and lower voltage lines under the UHV AC transmission line

are analyzed

and it is found that both methods can narrow the corridor width.