A rracticaj ntudy of an electromagnetic interference (EMI) problem from Saudi Arabia

Abstract

Electromagnetic Field interference (EMI) caused by electric transmission and distribution lines on neighboring metallic utilities such as communication cables, water, gas and oil pipelines became a major concern in Saudi Arabia due to the significant increase in the load, rapid and large power, water desalination and pipelines systems expansion, new discoveries of oil and gas resources, and short-circuits. The mechanisms of electromagnetic field interference between a power system network and a buried pipeline at low frequencies have been traditionally divided into three categories: inductive, conductive and capacitive coupling. Conventionally, the inductive interference is analyzed with a circuit model approach and the conductive interference is determined using appropriate grounding software. The inductive and conductive components are then added together. Cases arise in practice in which long electric power lines and pipelines, sharing the same corridor, follow curved path which intersect one another, diverge, recon verge, etc.., making them difficult to model accurately with a circuit model approach. Recently, field-theory-based software does away with the assumptions and accounts simultaneously for inductive, conductive and capacitive coupling between all the buried and aboveground elements modeled. This paper illustrates practically, what would be the interference effects from AC power lines in mainly metallic pipelines. The determination of interference effects in a typical right-of-way is a complex procedure requiring not only a good knowledge of conductor layout, power line and pipeline electrical characteristics and electrical system parameters, but also an accurate representation of the soil structure resistivity. A complete case study of a 230 KV transmission line EM1 effect on a oil buried pipeline will be presented. The paper outlines why should we observe the safety of people who come in vicinity of such pipelines, and why this EM1 studies are important and should be conducted and checked when ever and expansion is planned?, also, the safety of equipment connected to the pipeline is vely essential to both utilities and industries and it help saving tremendous amount of operation and maintenance (0 & M) costs.