Optimization of Spatial Configuration of Multistrand Cable Lines

Abstract

Skin and proximity effects have a considerable impact on current distribution in multistrand cable lines. Under unfavorable heat exchange conditions, some strands may be subject to excessive overheating, which may lead to serious malfunctions or even fires of the installation. The paper proposes a new criterion for a quick choice of spatial configurations, for which the effect might be minimized. A comprehensive analysis of literature cases is provided, including the recommendations of the U.S. National Code and the Canadian standard.

A Multiphysics Analysis of Coupled Electromagnetic-Thermal Phenomena in Cable Lines

“…• further validation of the barycenter criterion for optimal ampacity of multi-strand cable lines, outlined in Reference [7], considering the effect of harmonics and the presence of conducting shelves for placement of cables; a comparison of results obtained with the aforementioned criterion and with the VIS algorithm shall be carried out; and • FEM-based studies of more complicated cases (distorted current waveforms, chosen three phase configurations, consideration of conducting power cable tray, forced air flow etc.).…”

“…In the paper [7] a brief description of a laboratory stand used for practical experiments with chosen single-phase systems was given. In order not to repeat the description we include here only new relevant pieces of information.…”

“…The present paper is complementary to the previous work [7]. The aforementioned publication introduced a simplified approach to assess the optimal current distribution in low-voltage multi-strand cable lines, whereas the present contribution focuses on coupled electromagnetic-thermal modeling using commercial software.…”

“…As a representative example for the practical application of the presented method the results of coupled computations are provided for three spatial configurations (two cables per phase) considered previously in reference [7]. Some configurations (e.g., the two-row setup ABC/ABC) are not favorable, since they violate the barycenter criterion for uniform current distribution provided in the aforementioned paper.…”

“…The criterion may be easily implemented in a popular spreadsheet, or even checked using "by-hand" computations, thus there is no need to resort to sophisticated software tools like e.g., the Vector Immune Optimization method [8][9][10][11] or other global optimization algorithms [12][13][14][15][16][17][18]. However, as pointed in the Conclusion section of the paper [7], the final step of the design stage should be based on FEM computations that take into account the coupled electromagnetic-thermal phenomena. The present contribution thus fills the gap in this respect and provides additional information.…”