Challenge: two electromagnetic problems

AI Thread Summary
In a phase-to-neutral fault on a transmission line, the presence of a neutral wire can influence the magnetic field, potentially decreasing it due to the return path provided by the neutral. The discussion highlights that without a neutral line, a phase-to-neutral fault cannot occur. Regarding the second problem, the participants suggest that it involves refraction rather than reflection, indicating that the image of the point current source should be considered in the upper half-space. The complexities of soil resistivity and its impact on potential distribution are acknowledged, emphasizing the need for clarity in the problem's setup. Overall, the discussion centers on the implications of neutral wires in fault conditions and the behavior of electric fields in layered soil environments.
wine9
(a) When there is a phase-to-neutral fault on a transmission line, will the existence of the neutral wire increase or decrease the magnetic field under the transmission line? Why?

(b) Assuming that the whole space consists of an upper half space with soil resistivity r1 and a lower half space with soil resistivity r2, assuming further that a point current source, I, is located h meters away from the soil interface in the upper space, find the Earth potential at the image position of the point source in the lower space
 
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Hi wine9, sorry I'm completely lost at this.

(a)If the neutral line doesn't exist, then how can you have a phase-to-neutral fault?
(b)I think this is a refraction (not reflection) problem and so the image should be in the upper space.
 
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