Contributions to the control of AC stray currents corrosion

Practical aspects concerning the control of corrosion for underground metallic structures interfered with AC stray currents, have been studied. Technical solutions for the control of AC stray currents on underground metallic structures, both with and without cathodic protection, are proposed. These solutions are based on a silicon solid-state device which increases the cathodic protection effectiveness and simultaneously provides: electric safety of the metallic structure, drainage of DC stray currents to the grounding system and rectification of AC stray currents.