Proximity of O/head line to Water Pipeline 3

[dkle40h]

Hi,
Does anyone know how to quantify the effects of an o/head power line running adjacent to a pipeline? I have heard that the power line can change the corrosion patterns of the pipeline. I am busy designing an overhead line and was hoping to run the servitude adjacent to the servitude of the existing water pipeline to reduce the environmental impact. Any advice will be appreciated.
Kind Regards

 

[GordS]

The current on the O/h power line will magnetically induce voltages in adjacent parrallel items. To solve, you need to form the matrix of self and mutual inductances between the phase conductors and pipe and solve the resulting equations. IEEE 367 "Recommended Practice for Determining Electric Power Station GPR and Induced Voltage from a Power Fault" will give guidance in some of the equations you will need. Personally, I use the ATP program for this calculation because it inherently calculates the inductances for me. It has given me answers very close to measured values and values shared in published papers.

You need to look at steady state induced voltages as well as those induced during a fault. In the latter case, you will need to investigate touch potentials at the pipeline wherever it is normally accessable to the public.

You ned to know the powerline phase spacings, static wire and ground wire positions (if applicable),location w.r.t. the pipe, available fault, expected load current, load imbalance and how the power line and pipeline are grounded. As well, you need the wire and pipe characteristics ( resitivity, magnetic permeability, size)

In addition there is an electrostatic coupling that will be a concern during construction or pipe maintenance. One can expect a voltage on any section of pipe any time a section of pipe is isolated from ground ( such as if it were supported in a non conductive sling).

The concerns above are basically safety concerns. The induced voltage will also impact corrosion which is a whole other issue.

 

[jbartos]

Suggestion: Visit

http://www.dipra.org/pdf/ACPowerLines.pdf

for: an applicable concept

http://www.prci.com/publications/L51835e.htm

for: software

http://www.prci.com/publications/L51418e.htm

etc. for more info