ELF electromagnetic environment in power substations

Abstract

This paper presents a theoretical analysis of electromagnetic environments in power substations in service. A new analytical method is developed and applied to magnetic field calculations in 187-kV and 66-kV substations. Experimental results verify that the method offers a good prediction of the magnetic field profiles in the substations except for the areas where localized field sources exist. The analytical results show that the magnetic field strength depends to a great extent on how the load powers distribute on individual lines and buses, that the magnetic fields in substations have a three-dimensional characteristic, and that the predominant field component depends on the position of interest. Moreover, it is suggested that objects placed in substations are exposed not only to magnetic fields of high strength in comparison to those in houses or near the distribution networks but also to fields with several percent of harmonic distortion.

Residential exposure to 60‐Hz magnetic fields from appliances

“…Major advances have been made recently in the modeling of currentcarrying conductors in and around occupational and residential sites [Hayashi et al, 1989;Mader et al, 19901. These models have been successful in predicting actual magnetic-field densities due to transmission and distribution facilities and household wiring.…”

Computation of maximal magnetic field value generated by a power substation

“…If linear mediums are concerned, the ELF magnetic field value in each spatial point can be assessed superposing the contributions of all conductors divided in a certain number of straight segments [1][2][3][4][5]. A k-th straight segment with the current i k placed in the Cartesian three-dimensional co-ordinate system is shown in Figure 1.…”

“…ELF magnetic fields from power substations have been assessed via calculations or measurement procedures in many papers. Some of them are highlighted in this work [1][2][3][4][5], presenting a number of three-dimensional as well as contour plots. Nevertheless, they provided a useful description of the field characteristics, no technique incorporating certain optimization method for assessing the maximal magnetic field value has been applied in these papers.…”

Magnetic field measurements near a compact kiosk type substation

“…Particularly an analytical method based on Biot-Savart law for magnetic field calculation in 187kV and 66kV substations is demonstrated in [15], with a comparison between the theoretical results and experimental data. For the calculation of the magnetic fields the earth currents were neglected, the earth was regarded non magnetic and the currents were in phase with the voltage.…”