Reduction of the Environmental Impact of Electric Field Generated by High Voltage Power Transmission Lines

The growing interest in the negative environmental impact of overhead power lines of high and extra-high voltage stems from the increasing ecological awareness of societies. Consequently, a number of respective legal restrictions have been issued and actions have been undertaken to reduce this impact, especially in the electric field of the power frequency. The aim of this paper is to analyze the possibilities of reducing the width of electric field influence zones by changing the design parameters of power lines and defining the spatial distribution of its conductors. This analysis was carried out using the developed and experimentally verified models for determining the electric field and audible noise in the power line environment. The computational models were used to analyze the width of the electric field influence zones of 400 kV lines and the noise levels at the borders of these zones. The research focused on single and double circuit 400 kV power lines. It was revealed that a reduction in electric field emissions is accompanied by an increase in noise emission. However, the analyses confirmed that the width of the electric field influence zones can be significantly reduced if the most important design and construction parameters of the line are properly selected. The obtained conclusions are valid not only for 400 kV lines, but also set directions to follow when changing the parameters of high voltage transmission lines of other rated voltages (above 100 kV).