Electromagnetic voltage induction and mitigation on passive conductors from overhead transmission lines

Voltage induction on passive conductors, such as pipelines, has become a major problem with increased loads on power transmission lines. This has resulted in major efforts by utilities to mitigate these voltages to an acceptable level. Induced fields are calculated using the principle of mutual induction. Transmission line theory is utilized to cascade different sections of a conductor to give resultant voltages from multiple points of mitigation or dissimilar line sections. The model is general and may be used to predict voltage at any point on a line under the influence of an energized transmission line. Different types of mitigation may be studied and the model takes into account the interaction between points of mitigation. Computer programs are described to calculate induced fields and cascade sections for multiple mitigation. A case study is presented.