Estimating the environmental impacts of HVDC and UHVDC lines for large-scale wind power transmission considering height-dependent wind and atmospheric stability

Abstract

Due to the imbalance of China’s resources allocation, inter-provincial high voltage direct current (HVDC) transmission grid is considered to be the promising solution to solve to the large-scale wind power transmission, which could tackle the reverse regional distribution problem of energy resource and electricity load. In this contribution, a power law profile model of wind speed on embedded atmospheric stability is developed for calculating the height-dependent wind speed. The Monin-Obukhov length is introduced to determine the atmospheric stability. The ion flow environment model considering height-dependent wind speed is proposed to estimate the influence of height-dependent wind on ground-level electric field environment of DC transmission line and the iterative flux tracing method-finite difference is proposed to solve the model. It is observed that the stable, neutral and unstable atmospheric conditions have a large influence on transverse wind speed and then indirectly influence the electric field and ion current environment of DC lines. For the electromagnetic environment of the practical DC line used for the wind power transmission, the proposed model provides a reasonable agreement with measurements from a perspective of practical engineering application.