Technical Presentations

Evaluation of Electromagnetic Interferences Affecting Metallic Pipelines883

Abstract
This chapter presents some analysis of the modeling techniques used to evaluate the effects of electromagnetic interference phenomena that could occur when metallic pipelines are placed close to high-... see morevoltage power lines. The electric and magnetic fields produced by overhead power lines could perturb the normal operation of the metallic pipelines through induced currents and voltages. These perturbations could be dangerous for both pipeline operating personnel (as electrical hazard) and pipeline structural integrity (due to accelerated electrochemical corrosion phenomena). The chapter depicts the electromagnetic coupling mechanisms behind the abovementioned interference phenomena and how the induced voltages could be evaluated. A parametric analysis is showcased to highlight the influence of various geometrical and electrical parameters.

Tag(s): Electromagnetic Interference, Metallic Pipelines, Electric Fields, Magnetic Fields, Induced Voltages

Simulation of Inductive EM Interference Caused by an HVDC Underground Cable Link on a Railway System853

Abstract
Scope of the presentation is to present results regarding inductive electromagnetic interference (EMI) between a real HVDC link and the nearby communication cables of a railway system under pole-to-gr... see moreound fault conditions.
?he HVDC and the railway system route in parallel at a part of the onshore section of the HVDC link. The inductive EMI on the communication cable arises from magnetic field variation of the high-frequency components contained in the transient response of the fault current, excited by the HVDC link.

Consequently, it is expected that no inductive EMI will occur by the DC current in the case of the HVDC system normal operation (steady-state) either in bipolar or monopolar (current return though the electrode) mode. The induced transient voltages and currents are calculated using the Electromagnetic Transients Program (EMTP).

Tag(s): emi, wb cable, hvdc, interference

Induced Currents and Voltages in Underground Metallic Pipelines due to nearby Power Lines782

Abstract
During the last decades, environmental and economic reasons impose that gas or water pipelines share the same distribution paths with high voltage or medium voltage power lines, to restrain the financ... see moreial and the ecological costs. Therefore, the cases where underground metallic pipelines and power lines share proximal rights-of way for considerable lengths are a common practice.
The electromagnetic interference of power lines upon the metallic buried pipelines is an issue of priority, to avoid the development of induced voltages that could jeopardize the safety of the personnel and the integrity of the pipelines structure. Indeed, the developed voltages and currents can be dangerous for people who touch metallic structures connected with the pipelines or just stand nearby.

Moreover, the induced voltages can result in the corrosion of a pipeline due to electrochemical effect, leading to repair or/and replacement costs and environmental repercussions.

It is worth mentioning that the interference comprises an inductive, a conductive and a capacitive part. The capacitive part can be safely ignored in the case of buried pipelines, since the conductive component is considered only under fault conditions and affects the part of the pipeline near the faulted structure.

The inductive component is present both during faults and normal operating conditions and is the dominant one. Due to the inductive interference, voltages and currents are induced in a buried metallic pipeline.