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Pipe-type cable systems, including high-pressure fluid-filled (HPFF) and high-pressure gas-filled cables, are widely used for underground high-voltage transmission. These systems consist of insulated conductor cables within steel pipes, filled with pressurized fluids or gases for insulation and cooling. Despite their reliability, faults can occur due to insulation degradation, thermal expansion, and environmental factors. As many circuits exceed their 40-year design life, efficient fault localization becomes crucial. Fault location involves prelocation and pinpointing. Therefore, a novel pinpointing approach for pipe-type cable systems is proposed, utilizing accelerometers mounted on a steel pipe to capture fault-induced acoustic signals and employing the time difference of arrival method to accurately pinpoint the location of the fault. The experimental investigations utilized a scaled-down HPFF pipe-type cable system setup, featuring a carbon steel pipe, high-frequency accelerometers, and both mechanical and capacitive discharge methods for generating acoustic pulses. The tests evaluated the propagation velocity, attenuation, and pinpointing accuracy with the pipe in various embedment conditions. The experimental results demonstrated accurate fault pinpointing in the centimeter range, even when the pipe was fully embedded, with the acoustic pulse velocities aligning closely with the theoretical values. These experimental investigation findings highlight the potential of this novel acoustic pinpointing technique to improve fault localization in underground systems, enhance grid reliability, and reduce outage duration. Further research is recommended to validate this approach in full-scale systems.
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This content will become publicly available on May 18, 2026
Partial Discharge Localization along Medium Voltage Cables
Statistics indicate that more than 85% of equipment failures are related to insulation failure. Such faults can lead to brownouts and blackouts and in the transportation electrification context can also impact the safety of personnel or jeopardize missions, which is highly unacceptable. In this regard, predicting a fault before it occurs to do planned maintenance is needed where partial discharge (PD) activity can be used as an indicator. The paper presents a model based on the time of arrival (ToA) approach for PD localization in medium voltage (MV) cables which are a critical component in powertrains and distribution grid connections. The cable considered, which is a three-phase MV cable with three single-core armored copper conductors is modeled using a frequency-dependent wideband model in EMTP. The model accurately represents the cable's behavior by incorporating the skin effect and the impact of semiconducting layers on signal propagation. The attenuation coefficient is calculated for varying frequencies and lengths to evaluate the effect of the semiconducting metallic screen and attenuation voltages. An empirical relationship is developed by injecting PD signals at predefined locations and analyzing arrival time differences at cable terminals, linking propagation velocity, cable length, and ToA. The proposed methodology ensures precise PD localization, highlighting its potential for enhancing diagnostic accuracy in cable systems.
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- Award ID(s):
- 2306093
- PAR ID:
- 10652895
- Publisher / Repository:
- IEEE
- Date Published:
- Page Range / eLocation ID:
- 834 to 839
- Format(s):
- Medium: X
- Location:
- Houston, TX, USA
- Sponsoring Org:
- National Science Foundation
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