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Title: Stray current interference control for HVDC earth currents

Abstract

High-voltage direct current (HVDC) transmission lines exist around the world, with several in the US. When one conductor must be taken out of operation (in case of emergency), the earth may be used as an alternate conductor. The earth current may be accumulated on and discharged from underground metallic structures that cross the voltage gradient created by the current. Test results on two lines showed that stray current interference is not a major problem if mitigated properly.

Authors:
 [1];  [2]
  1. PSG Corrosion Engineering/Corrpro Cos., Detroit, MI (United States)
  2. Corrpro Companies Inc., Spring, TX (United States)
Publication Date:
OSTI Identifier:
72866
Resource Type:
Journal Article
Resource Relation:
Journal Name: Materials Performance; Journal Volume: 34; Journal Issue: 6; Other Information: PBD: Jun 1995
Country of Publication:
United States
Language:
English
Subject:
24 POWER TRANSMISSION AND DISTRIBUTION; HVDC SYSTEMS; LEAKAGE CURRENT; CONTROL; POWER TRANSMISSION LINES; ELECTRIC GROUNDS; UNDERGROUND FACILITIES; MINNESOTA; NORTH DAKOTA; PERFORMANCE TESTING

Citation Formats

Fitzgerald, J.H. III, and Kroon, D.H. Stray current interference control for HVDC earth currents. United States: N. p., 1995. Web.
Fitzgerald, J.H. III, & Kroon, D.H. Stray current interference control for HVDC earth currents. United States.
Fitzgerald, J.H. III, and Kroon, D.H. 1995. "Stray current interference control for HVDC earth currents". United States. doi:.
@article{osti_72866,
title = {Stray current interference control for HVDC earth currents},
author = {Fitzgerald, J.H. III and Kroon, D.H.},
abstractNote = {High-voltage direct current (HVDC) transmission lines exist around the world, with several in the US. When one conductor must be taken out of operation (in case of emergency), the earth may be used as an alternate conductor. The earth current may be accumulated on and discharged from underground metallic structures that cross the voltage gradient created by the current. Test results on two lines showed that stray current interference is not a major problem if mitigated properly.},
doi = {},
journal = {Materials Performance},
number = 6,
volume = 34,
place = {United States},
year = 1995,
month = 6
}
  • High voltage direct current transmission lines exist in various parts of the world. There are several in the United States. While designed to carry all the current in the wires, in case of emergency or if it is necessary to take one conductor out of service, earth may be used as a conductor. The earth current may be accumulated on, conducted by and discharged from underground metallic structures that cross the voltage gradient created by the current. This paper describes ground current operation tests made in June 1992 on two HVdc lines that run from Minnesota to North Dakota asmore » a follow up to initial tests in 1976 on one line and in 1978 for the other. Results showed that stray current interference was not a major problem. Effects of the stray current interference were mitigated by distance of the structures from the earth electrodes, adequate cathodic protection and use of automatic potential controlled mitigation rectifiers. The tests showed the importance of close cooperation between electric companies and operators of underground facilities. They also showed that should earth be used as a conductor, special mitigative measures will be necessary.« less
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  • Stray currents, mostly known for their detrimental corrosion affects on the underground structures, can be effectively controlled by the implementation of specific measures at both the source of generation and at the affected structure(s). This paper discusses the most serious sources of stray current generation, the resulting problems and the numerous control methods that can be utilized to minimize corrosion and safety problems. Safety concerns associated with dc power systems are also discussed.
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