Influence Research on Induced Voltage of Multi UHVDC Transmission Lines to the Power Line Under Construction in the Same Corridor

[Introduction] Multi power transmission lines arranged in the same corridor could avoid the land division and reduce the adverse effect on the local planning and development, but the personal safety of operators in the process of towers and conductors erection of subsequent power lines should be seriously considered as a result of induced voltage of the previous energized transmission lines. [Method] One DC transmission line under construction was taken as an example, electrostatic induced voltage generated from multi UHVDC transmission lines nearby in the same corridor were studied and calculated. The influence factors including the operating mode of UHVDC lines, line spacing from the energized power lines and length of stringing conductors were analyzed at the same time. [Result] The results show that the induced voltage got significantly high from adjacent UHVDC lines, and operation mode of energized lines played an important part; the less line spacing reduce, the higher induced voltage reach; the steady-state current from ion current density generated by UHVDC lines flowing through construction equipments have nearly less impact to constructors. Induced voltage of the stringing conductors will be paid much attention to when stringing and conductors and equipments should be grounded effectively. [Conclusion] The research results also have guiding significance to power lines′ construction which be adjacent to live lines.