Electromagnetic environment study for 750 kV extra high voltage AC transmission lines

The CDEGS software package was used to simulate the electromagnetic environment of the 750 kV transmission line.Based on the three-phase double-circuit overhead transmission line model,the influences of the conductor-to-ground height,the conductor sequence,numbers and spacing of the split conductors,and the diameter of the sub-conductor on the power frequency electric field and magnetic field,the radio interference(RI),and the audible noise(AN) are analyzed.Measures to improve the electromagnetic environment are proposed.The power frequency electric field limits were used to determine the width of the line corridor,and the RI and AN under different weather conditions such as heavy rain,wet conductor,and fair weather are compared.Simulations show that the AN and the power frequency electric field are the major factors affecting the electromagnetic environment of the 750 kV transmission line.