| 1. |
- Nilsson, Börje, et al.
(författare)
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Simulation of electromagnetic pulses in waveguides at large distances
- 2011
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Ingår i: International Conference on Electromagnetics in Advanced Applications (ICEAA11). - : IEEE Press. - 9781612849768 ; , s. 640-643
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Konferensbidrag (refereegranskat)abstract
- This paper presents accurate analytical expressions in the time domain for discrete electromagnetic waveguide modes for large distances together with a discussion of the errors. The main application is source localization for high voltage direct current submarine power cables. The research behind this paper is part of the project “Fundamental wave modelling for signal estimation on lossy transmission lines” funded by the Swedish Research Council and ABB High Voltage Cables AB in Sweden.
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| 2. |
- Nordebo, Sven, et al.
(författare)
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Electromagnetic dispersion modeling and measurements for HVDC power cables
- 2011
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- This paper provides a general framework for electromagnetic modeling, computation and measurements regarding the wave propagation characteristics of High-Voltage Direct Current (HVDC) power cables. The modeling is focused on very long (10 km or more) HVDC power cables and the relevant frequency range is therefore in the low-frequency regime of about 0-100 kHz. An exact dispersion relation is formulated together with a discussion on practical aspects regarding the computation of the propagation constant and the related characteristic impedance. Experimental time-domain measurement data from an 80 km long HVDC power cable is used to validate the model. It is concluded that a single-mode transmission line model is not adequate to account for the mismatch between the power cable and the instrumentation. A mismatch calibration procedure is therefore devised to account for the connection between the measurement equipment and the cable. A dispersion model is thus obtained that is accurate for early times of pulse arrival. To highlight the potential of accurate electromagnetic modeling, an example of high-resolution length-estimation is discussed and analyzed using statistical methods based on the Cramer-Rao lower bound. The analysis reveals that the estimation accuracy based on the present model (and its related model error) is in the order of 100 m for an 80 km long power cable, and that the potential accuracy using a perfect model based on the given measurement data is in the order of centimeters.
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| 3. |
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| 4. |
- Nordebo, Sven, et al.
(författare)
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Wave modeling and fault localization for underwater power cables
- 2011
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Ingår i: 2011 IEEE-APS Topical Conference on Antennas and Propagation in Wireless Communications (APWC). - : IEEE Press. - 9781457700460 ; , s. 698-701
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Konferensbidrag (refereegranskat)abstract
- This paper describes some preliminary results regarding Time-Domain pulse Reflection (TDR) measurements and modeling performed on the Baltic Cable submarine HVDC link between southern Sweden and northern Germany. The measurements were conducted in collaboration between the Linnaeus University, Lund University, Baltic Cable AB and ABB High Voltage Cables AB, and is part of the research project: “Fundamental wave modeling for signal estimation on lossy transmission lines”. Preliminary results on measurements and modeling are included here, as well as a first numerical study regarding the low-frequency dispersion characteristics of power cables. The numerical study shows that the finite conductivity of the cable lead shield has a great impact on the losses at low frequencies (0-1 kHz), and that the low-frequency asymptotics of the propagation constant is consistent with common propagation models based on the skin-effect.
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