الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
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, the induced AC voltage on the
pipelines due to inductive, and conductive coupling in steady-state and fault 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. This work further utilizes a comparative analysis of two different
mitigation units: a potassium hydroxide polarization cell (KOH-PC) and the solid-state polarization cell (SSPC) to decide which one of these methods is more suitable for cathodic protection distribution. This study
also explores the potential of the hill-climbing algorithm in optimizing the two proposed mitigation units’
parameters to guarantee better CP performance. Moreover, the effect of changing the numbers and parameters
of polarization cells on both induced AC voltages and CP performance is introduced to achieve a global
minimum DC voltage degradation. Further, a comparative performance evaluation of various operating
conditions considering the variation of both phase conductor transposition and loading capacity on each
transmission line is implemented. An integrated system consists of power electronic circuits and distributed
intelligent controllers designed to utilize the harmful induced AC voltage to be useful for pipeline protection
against AC corrosion and compensating for the deterioration of the DC CP voltage. This system installs at
each highest pipeline’s induced voltage point. Moreover, each system has its controller that controls the
discharged energy. Some of this energy is converted from the alternating form (AC) to direct form (DC) to
enhance the cathodic protection performance. At the same time, the remaining part of this energy drains into
the soil via the earthing grid. The distributed cathodic protection integrated system (DCPIS) may use to
illustrate the proposed solution. It is essential to make the communication between all DCPISs, and the main
impressed current cathodic protection units (MICCPUs), that connected to the utility grid for sustaining the
CP performance within the acceptable limits with minimizing the consumed energy from the grid. In this
study, different controllers such as the artificial neural network, a fuzzy logic controller, and adaptive neurofuzzy inference system controllers have been implemented. Two key performance indicators have been
investigated to show the superiority of these controllers, where the total discharged energy per annum (DEyear)
from the pipeline to the soil, and the total saved energy per year from the utility (SEyear). The proposed
model’s performance is implemented through modeling and simulating on MATLAB software with the
experimental measurements.