Robust Analog DC Isolator for Cathodic Protection Applications

To provide cathodic protection (CP) for gas and oil underground pipelines, a direct current (DC) isolator is needed to isolate the main CP converter from the earth around the pipeline. The DC isolator, proposed in this paper, consists of four parts: a second-order low-pass active filter, voltage level shifter, pulse-width-modulation (PWM) controller, and a ground isolator. This converter is designed to accurately provide an isolated near-ground...