Acoustic waveguide technique for sensing incipient faults in underground power-transmission cables: including acousto-optic techniques. Final report
Abstract
The feasibility of using acoustic waveguide techniques for sensing incipient faults in underground power transmission cables was determined. Theoretical and practical studies were made of both the acoustic emission spectrum signatures associated with cable incipient faults, and the attenuation of acoustic waves in waterfilled metal tubes used as waveguides. Based on critical data, it can be estimated that in favorable circumstances, the acoustic waveguide system would only be useful for sensing incipient faults in underground cables of approx. 800 meters (approx. 0.5 miles) or less in length. As underground power transmission cables are often several kilometers in length, it was clear at this stage of the study, that simple acoustic waveguide sensing techniques would not be adequate, and some modification would be needed. With DOE approval it was decided to investigate acousto-optic sensing techniques in order to extend the detection range. In particular, a system in which acoustic emissions from cable incipient faults impinge on a fiber-optic lightguide and locally change its refractive indes, and as a consequence, modulate laser light transmitted along the light guide. Experiments based on this concept were successful, and it has been demonstrated that it is possible to sense acoustic emissions with energy levels belowmore »
- Authors:
- Publication Date:
- Research Org.:
- Westinghouse Research and Development Center, Pittsburgh, PA (USA)
- OSTI Identifier:
- 6072394
- Report Number(s):
- DOE/ET/29335-T1
ON: DE81029626
- DOE Contract Number:
- AC01-78ET29335
- Resource Type:
- Technical Report
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 24 POWER TRANSMISSION AND DISTRIBUTION; ELECTRIC CABLES; ACOUSTIC MONITORING; UNDERGROUND POWER TRANSMISSION; ACOUSTIC DETECTION; ELECTRICAL FAULTS; FIBER OPTICS; HELIUM-NEON LASERS; MEASURING METHODS; POWER TRANSMISSION LINES; ACOUSTIC MEASUREMENTS; CABLES; CHARGED PARTICLE DETECTION; CONDUCTOR DEVICES; DETECTION; ELECTRICAL EQUIPMENT; EQUIPMENT; GAS LASERS; LASERS; MONITORING; POWER TRANSMISSION; RADIATION DETECTION; 200301* - Power Transmission & Distribution- AC Systems, EHV & UHV- (-1989)
Citation Formats
Harrold, R T. Acoustic waveguide technique for sensing incipient faults in underground power-transmission cables: including acousto-optic techniques. Final report. United States: N. p., 1981.
Web.
Harrold, R T. Acoustic waveguide technique for sensing incipient faults in underground power-transmission cables: including acousto-optic techniques. Final report. United States.
Harrold, R T. Tue .
"Acoustic waveguide technique for sensing incipient faults in underground power-transmission cables: including acousto-optic techniques. Final report". United States.
@article{osti_6072394,
title = {Acoustic waveguide technique for sensing incipient faults in underground power-transmission cables: including acousto-optic techniques. Final report},
author = {Harrold, R T},
abstractNote = {The feasibility of using acoustic waveguide techniques for sensing incipient faults in underground power transmission cables was determined. Theoretical and practical studies were made of both the acoustic emission spectrum signatures associated with cable incipient faults, and the attenuation of acoustic waves in waterfilled metal tubes used as waveguides. Based on critical data, it can be estimated that in favorable circumstances, the acoustic waveguide system would only be useful for sensing incipient faults in underground cables of approx. 800 meters (approx. 0.5 miles) or less in length. As underground power transmission cables are often several kilometers in length, it was clear at this stage of the study, that simple acoustic waveguide sensing techniques would not be adequate, and some modification would be needed. With DOE approval it was decided to investigate acousto-optic sensing techniques in order to extend the detection range. In particular, a system in which acoustic emissions from cable incipient faults impinge on a fiber-optic lightguide and locally change its refractive indes, and as a consequence, modulate laser light transmitted along the light guide. Experiments based on this concept were successful, and it has been demonstrated that it is possible to sense acoustic emissions with energy levels below one micro-joule. A practical test of this system in the laboratory using a section of compressed gas-insulated cable with an internal flashover was successfully carried out. Long distance fault sensing with this technique should be feasible as laser light can be transmitted several kilometers in fiber optic lightguides. It is believed that laser-acousto-optic fault sensing is a viable technique which, with development, could be applied for fault sensing in power cables and other apparatus.},
doi = {},
url = {https://www.osti.gov/biblio/6072394},
journal = {},
number = ,
volume = ,
place = {United States},
year = {1981},
month = {9}
}