Influence factors and reasonable arrangement of corridor width of ±800 kV HVDC and 750 kV HVAC hybrid transmission lines

With the development of economy and the increased demand of power energy, it is unavoidable that high-voltage direct current (HVDC) and high-voltage alternating current (HVAC) transmission lines are in the same corridor. In order to minimise the land resource and meet the requirements of the electromagnetic environment, it is necessary to accurately predict the hybrid electric field under the hybrid transmission lines. The +/- 800kV HVDC and 750kV HVAC parallel transmission lines of parallel erection are chosen to be analysed. The corridor width with a different separation distance is calculated, and the minimum corridor width under this voltage-level combination is obtained according to the control value of the hybrid electric field recommended at home and abroad in a non-residential area. Increasing the height of DC or AC lines can reduce the corridor width. At a fixed separation distance, the minimum height of the AC line can be obtained when the height of the DC line is set at a certain value. Meanwhile the change of the corridor width is analysed with different heights of DC lines and AC lines. Based on the above analysis, the reasonable arrangement is made.