پیدانلود رایگان ترجمه مقاله اثرات پیکربندی های اسپن و کشش هادی روی توزیع میدان مغناطیسی (سال ۲۰۱۲)

اثرات پیکربندی های اسپن و کشش هادی روی توزیع میدان مغناطیسی زیر خطوط انتقال هوایی

The Effects of the Span Configurations and Conductor Sag on the Magnetic-Field Distribution under Overhead Transmission Lines

Abstract

Ground level electric and magnetic-fields from overhead power transmission lines are of increasingly important considerations in several research areas due to their impact on health and environmental issues. The paper presents a more generalized technique to calculate the magnetic-field generated by power transmission lines in three dimension coordinates. This technique has been evolved, formulated, analyzed and applied to a suggested 500-kV single circuit transmission line to evaluate the effects of line topology and terrain topography on the computed magnetic-field. The results are compared with two-dimensions technique.

۱ Introduction

PRECISE analytical modeling and quantization of electric and magnetic-fields produced by overhead power transmission lines are important in several research areas [1]- [3]. Considerable research and public attention concentrated on possible health effects of extremely low frequency (ELF) electric and magnetic-fields [4-5]. An analytical calculation of the magnetic-field produced by electric power lines is produced in [6] and [7], which is suitable for flat, vertical, or delta arrangement, as well as for hexagonal lines. Also the estimation of the magnetic-field intensity at locations under and far from the two parallel transmission lines with different design arrangements is presented in [8]. The effects of conductors sag on the spatial distribution of the magnetic-field are presented in [9], in case of equal heights of the towers, equal spans between towers and the power transmission lines’ spans being always parallel to each others.

In this paper, the magnetic-field is calculated by two different techniques; 2-D straight line technique and 3-D integration technique, where the effect of the sag in the magnetic-fields calculation, and the effects of unequal span distances between the towers, unequal towers heights, and when the power transmission lines’ spans are not in straight line are investigated. The proposed three-dimension integration technique has been applied to different cases in order to justify its generalization for magnetic-field produced by actual transmission line configuration, arrangement, and terrain topography, and also has been applied to a suggested 500-kV single circuit overhead transmission line as an application case study.