With the expansion of electricity demand

transmission corridors are becoming scarce.AC and DC circuits running parallel to each other and sharing the same right-of-way or even the same tower become a possible option.Due to the existence of the adjacent line

space electromagnetic field and corona of another line may be changed.Different characteristics of two line types make the electromagnetic field of transmission corridors become more complex.Hybrid line is viewed as a whole.The calculation contains surface gradient

ground level electric field

radio interference and audible noise.Interaction between the two line types is considered.The calculation results show that the interaction is mainly concentrated in the inner corridor.In the role of DC electric field

AC electric field is no longer symmetrical and ground level electric field is significantly enhanced.Under the negative DC voltage

the positive corona of the waveform is significantly strengthened

and it is inhibited under the positive DC voltage.It is better to erect the positive DC line near AC line.