Pipelines for oil or gas are often build for many kilometres in parallel to high voltage overhead lines. Modern ones are well isolated by polyethylene coating for corrosion protection reasons. Especially if short-circuit or lightning currents are present on the overhead lines the influenced voltage on the pipelines can reach very high magnitudes. To prevent deadly over voltages pipelines are earthed every view kilometre. As this earthing is usually performed by 100 m deep drillings to be effective, it can be rather cost effective. In this paper, a self-written software is used to calculated pipeline over voltages and to optimize the number of earthing points.
As nowadays AC overhead lines get sometimes upgrade to DC applications for capacity reasons expectable changes in influenced pipeline voltages are simulated and discussed for short-circuit and lightning conditions.

• Prof. Dr.-Ing. Thomas Hücker (Projektleitung)

• Steffel KKS