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Abstract During the last years, the interest in the environment and biological effects of the exposure to the magnetic fields caused by electric power systems and installations on people and animals has been increased because of the results of a number of studies which indicated possible harmful effects due to the exposure to these fields. Many ases of paralled and crossing power lines can be found. The prevailing magnetic field profiles in such cases are expected to be different when compared to the cases of single lines. Accordingly, the current thesis considers the evaluation of magnetic fields in the vicinity of parallel and crossing lines as can be found in the Egyptian power system by using an accurate three-dimension (3-D)cpmputational techniquie. Magnetic field distributions under different parallel power lines; parallel 500kVlines lines,parallel 220kV lines, parallel 66 kV lines, parallel 11kV lines, parallel 220& 66kVlines and parallel 66 & 11kV,lines are developed and analyzed. Effects of spacing between the parallel lines, phase arrangement, current direction and line loading are also considered. The impacts of ordinary tower staggering in the cases of parallel 220 766kV lines and parallel 667 11kV, lines are evaluated. In addition, a proposed intended staggering technique, applied at parallel 500kVlines, is also presented. Magnetic field distributions under crossing power lines; crossing 55 & 66 kV lines, crossing 220 & kV lines and crossing 66&11 kV lines developed and analyzed. Effects of phase arrangement, current direction and line loading are also taken into account. |