Impact of High Voltage Overhead Line Design on Pipeline Security
Proceedings Publication Date
The changing focus of energy politics to renewable energy and the constantly rising demand for energy has been leading to the development of existing high voltage stations, overhead power lines and cables as well as to the construction of new equipment for the transportation of additional current load. Therefore, the conductive and inductive interference near buried isolated metallic pipelines is rising which causes an increase in AC pipeline interference potential. This has an impact on the operation of pipelines. Increased voltages on a pipeline are a danger to people and pipeline system components. In addition, the higher inductive interference may raise the AC corrosion risk on the pipeline itself. In this case higher inspection and maintenance costs arise because of material corrosion and, in a worst case scenario, it may cause an additional threat to the environment. Within Austria and Europe exist standards and guidelines (EN 50443 , EN 15280 ) which limit the maximum voltage for long term and short term interference. If the pipeline interference voltage is within the limits no further actions are required and no further costs are generated. With newly built or extended high voltage overhead lines the maximum current for normal operations and short-circuit-situations can increase fundamentally. A precise method is needed to calculate the inference potential of a pipeline to find (only) the necessary measures for pipeline protection to avoid endangering people and material. It can be shown that the positioning and, for long term interference, the overhead line phase conductor arrangement are decisive factors when calculating the inference potential. Current mathematical models and software simulations show that varying pipeline coating and the ambience specific soil resistivity may cause a big fluctuation in the pipeline interference voltage.