Influence of Current-Dependent AC Resistance and Emissivity on Temperature Estimation of a Single-Layer ACSR Conductor
Research Article  ·  Published: 03 August 2026
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ICCK Transactions on Electric Power Networks and Systems
Volume 2, Issue 3, 2026: 116-127
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Influence of Current-Dependent AC Resistance and Emissivity on Temperature Estimation of a Single-Layer ACSR Conductor

1 Faculty of Technical Sciences, University of Priština in Kosovska Mitrovica, RS-38220 Kosovska Mitrovica, Serbia
* Corresponding Author: Miloš J. Milovanović, [email protected]
Volume 2, Issue 3

Article Information

Abstract

This paper investigates the influence of temperature- and current-dependent variations in alternating current (AC) resistance on the estimation of the operating temperature of aluminium conductor steel-reinforced (ACSR) conductors, with particular emphasis on the differences arising from the use of tabulated and experimentally determined resistance characteristics. Special attention is devoted to the current dependence of AC resistance in the single-layer ACSR conductor 48-AL1/8-ST1A, where pronounced resistance variations occur due to the electromagnetic interaction between the aluminum strands and the steel core. Experimental investigations were conducted under controlled laboratory conditions using a dedicated measurement system capable of the synchronized acquisition of electrical and thermal quantities in real time. Based on the obtained measurements, AC resistance characteristics were determined as functions of both conductor temperature and current, and their influence on conductor temperature estimation was subsequently evaluated. The results demonstrate that neglecting the current dependence of AC resistance may lead to conductor temperature estimation errors of up to approximately 2.5~°C under current loadings close to the rated value, indicating that this effect should not be disregarded in thermal analyses of single-layer ACSR conductors. However, the study also reveals that conductor emissivity has a substantially larger influence on temperature estimation. Specifically, varying the assumed conductor surface emissivity from 0.3 to 0.9 results in calculated conductor temperature differences exceeding 15 °C, significantly outweighing the influence of current-dependent AC resistance. The obtained findings indicate that accurate determination of conductor emissivity is essential for reliable thermal analysis and Dynamic Line Rating (DLR) applications, while the use of experimentally determined AC resistance characteristics further improves the accuracy of conductor temperature and ampacity assessments.

Graphical Abstract

Influence of Current-Dependent AC Resistance and Emissivity on Temperature Estimation of a Single-Layer ACSR Conductor

Keywords

alternating current (AC) resistance aluminum conductor steel-reinforced (ACSR) conductor dynamic line rating (DLR) conductor emissivity

Data Availability Statement

Data will be made available on request.

Funding

This work was supported by the Ministry of Science, Technological Development and Innovation of the Republic of Serbia under Contract No. 451-03-34/2026-03/200155.

Conflicts of Interest

Miloš J. Milovanović served as an Associate Editor of the ICCK Transactions on Electric Power Networks and Systems at the time of manuscript submission. To ensure the integrity of the peer-review process, Miloš J. Milovanović was not involved in the editorial handling, peer review, or decision-making process for this manuscript, which was handled independently by another editor. The remaining authors declare no conflicts of interest.

AI Use Statement

The authors declare that no generative AI was used in the preparation of this manuscript.

Ethical Approval and Consent to Participate

Not applicable.

References

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Cite This Article

APA Style
Milovanović, M. J., Jovanović, A. D., & Perović, B. D. (2026). Influence of Current-Dependent AC Resistance and Emissivity on Temperature Estimation of a Single-Layer ACSR Conductor. ICCK Transactions on Electric Power Networks and Systems, 2(3), 116-127. https://doi.org/10.62762/TEPNS.2026.632689
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Compatible with EndNote, Zotero, Mendeley, and other reference managers
TY  - JOUR
AU  - Milovanović, Miloš J.
AU  - Jovanović, Andrijana D.
AU  - Perović, Bojan D.
PY  - 2026
DA  - 2026/08/03
TI  - Influence of Current-Dependent AC Resistance and Emissivity on Temperature Estimation of a Single-Layer ACSR Conductor
JO  - ICCK Transactions on Electric Power Networks and Systems
T2  - ICCK Transactions on Electric Power Networks and Systems
JF  - ICCK Transactions on Electric Power Networks and Systems
VL  - 2
IS  - 3
SP  - 116
EP  - 127
DO  - 10.62762/TEPNS.2026.632689
UR  - https://www.icck.org/article/abs/TEPNS.2026.632689
KW  - alternating current (AC) resistance
KW  - aluminum conductor steel-reinforced (ACSR) conductor
KW  - dynamic line rating (DLR)
KW  - conductor emissivity
AB  - This paper investigates the influence of temperature- and current-dependent variations in alternating current (AC) resistance on the estimation of the operating temperature of aluminium conductor steel-reinforced (ACSR) conductors, with particular emphasis on the differences arising from the use of tabulated and experimentally determined resistance characteristics. Special attention is devoted to the current dependence of AC resistance in the single-layer ACSR conductor 48-AL1/8-ST1A, where pronounced resistance variations occur due to the electromagnetic interaction between the aluminum strands and the steel core. Experimental investigations were conducted under controlled laboratory conditions using a dedicated measurement system capable of the synchronized acquisition of electrical and thermal quantities in real time. Based on the obtained measurements, AC resistance characteristics were determined as functions of both conductor temperature and current, and their influence on conductor temperature estimation was subsequently evaluated. The results demonstrate that neglecting the current dependence of AC resistance may lead to conductor temperature estimation errors of up to approximately 2.5~°C under current loadings close to the rated value, indicating that this effect should not be disregarded in thermal analyses of single-layer ACSR conductors. However, the study also reveals that conductor emissivity has a substantially larger influence on temperature estimation. Specifically, varying the assumed conductor surface emissivity from 0.3 to 0.9 results in calculated conductor temperature differences exceeding 15 °C, significantly outweighing the influence of current-dependent AC resistance. The obtained findings indicate that accurate determination of conductor emissivity is essential for reliable thermal analysis and Dynamic Line Rating (DLR) applications, while the use of experimentally determined AC resistance characteristics further improves the accuracy of conductor temperature and ampacity assessments.
SN  - 3070-2607
PB  - Institute of Central Computation and Knowledge
LA  - English
ER  - 
BibTeX Format
Compatible with LaTeX, BibTeX, and other reference managers
@article{Milovanovi2026Influence,
  author = {Miloš J. Milovanović and Andrijana D. Jovanović and Bojan D. Perović},
  title = {Influence of Current-Dependent AC Resistance and Emissivity on Temperature Estimation of a Single-Layer ACSR Conductor},
  journal = {ICCK Transactions on Electric Power Networks and Systems},
  year = {2026},
  volume = {2},
  number = {3},
  pages = {116-127},
  doi = {10.62762/TEPNS.2026.632689},
  url = {https://www.icck.org/article/abs/TEPNS.2026.632689},
  abstract = {This paper investigates the influence of temperature- and current-dependent variations in alternating current (AC) resistance on the estimation of the operating temperature of aluminium conductor steel-reinforced (ACSR) conductors, with particular emphasis on the differences arising from the use of tabulated and experimentally determined resistance characteristics. Special attention is devoted to the current dependence of AC resistance in the single-layer ACSR conductor 48-AL1/8-ST1A, where pronounced resistance variations occur due to the electromagnetic interaction between the aluminum strands and the steel core. Experimental investigations were conducted under controlled laboratory conditions using a dedicated measurement system capable of the synchronized acquisition of electrical and thermal quantities in real time. Based on the obtained measurements, AC resistance characteristics were determined as functions of both conductor temperature and current, and their influence on conductor temperature estimation was subsequently evaluated. The results demonstrate that neglecting the current dependence of AC resistance may lead to conductor temperature estimation errors of up to approximately 2.5~°C under current loadings close to the rated value, indicating that this effect should not be disregarded in thermal analyses of single-layer ACSR conductors. However, the study also reveals that conductor emissivity has a substantially larger influence on temperature estimation. Specifically, varying the assumed conductor surface emissivity from 0.3 to 0.9 results in calculated conductor temperature differences exceeding 15 °C, significantly outweighing the influence of current-dependent AC resistance. The obtained findings indicate that accurate determination of conductor emissivity is essential for reliable thermal analysis and Dynamic Line Rating (DLR) applications, while the use of experimentally determined AC resistance characteristics further improves the accuracy of conductor temperature and ampacity assessments.},
  keywords = {alternating current (AC) resistance, aluminum conductor steel-reinforced (ACSR) conductor, dynamic line rating (DLR), conductor emissivity},
  issn = {3070-2607},
  publisher = {Institute of Central Computation and Knowledge}
}

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