The problem of AC corrosion remains motivating for researchers because many factors influence the corrosion
rate for buried pipelines due to the interference with overhead high voltage transmission lines (OHVTLs). Many
researchers study the mechanisms of induced alternating current (AC) voltages, which are summarized as
capacitive, inductive, and conductive coupling. In this work, only the induced AC voltage on the pipelines due to
inductive coupling in steady-state conditions is studied. A holistic mathematical model for the pipelines, power
lines, mitigation equipment for the induced voltage, and cathodic protection (CP) is illustrated. Potassium hydroxide
polarization cells are electrically represented because these cells are considered the most common
mitigation device for discharging the induced AC voltage from the pipeline to the soil. The overall model is
implemented using MATLAB. The results show the profiles of induced AC voltage along the pipeline, the CP for
the pipeline, the points of maximum voltage, and the influence of installing the AC mitigation units on the CP
performance. |
