Comparative Analysis of Inductance and Capacitance in Single and Bundled Conductors in Different Configuration Using Excel-Based Modelling

Abstract

This paper offers a comparative analysis of inductance and capacitance in both single and bundled conductors utilised in overhead transmission lines. The research centres on assessing the influence of conductor configuration on line parameters, which are essential for optimising power transmission efficiency. I used Microsoft Excel to make an analytical model that could figure out inductance and capacitance by changing important factors like the spacing, radius, and geometric mean radius (GMR) of the conductors. The idea of equivalent GMR was used to accurately show multi-conductor setups for bundled conductors. The analysis shows that bundled conductors have much lower inductance and much higher capacitance than single conductors. The enhanced performance is due to the larger effective radius and lower electric field intensity in bundled configurations. Graphical analysis shows even more how line parameters change based on spacing and conductor arrangement. The results of this study show that bundled conductors are better for high-voltage transmission systems because they reduce losses and make the system work better overall. The suggested Excel-based method is a simple and useful way to look at transmission line parameters. It can also be used for more optimisation studies.

Introduction

The text explains the importance of inductance and capacitance in electric power transmission lines, which are essential for efficient, stable, and reliable electricity delivery from power plants to consumers.

It highlights that these electrical parameters depend on conductor properties such as spacing, radius, and configuration. As power demand has increased, modern transmission systems use bundled conductors (multiple sub-conductors per phase) instead of single conductors, especially in EHV and UHV systems. Bundled conductors improve performance by reducing inductance, increasing capacitance, and lowering losses such as corona discharge and radio interference.

The study compares single and bundled conductor configurations using analytical calculations (implemented in Excel) by varying parameters like spacing and geometric mean radius (GMR). It uses standard formulas for calculating inductance and capacitance in three-phase transmission lines, including symmetrical, unsymmetrical, and double-circuit systems.

The theory section explains that:

• Inductance arises from magnetic fields around current-carrying conductors and affects voltage drop in AC systems.
• Capacitance is formed between conductors and the ground, influencing charging current and system behavior.

The methodology involves computing line parameters for different configurations, analyzing results through tables and graphs, and comparing performance.

Conclusion

For the purpose of this experiment, a comparison is made of the inductance and capacitance of transmission lines for different conductor configurations, namely the single conductor, bundled conductor, and double circuit. The calculation is done by the Excel method, where the effect of spacing, geometric mean radius, and geometric mean distance is considered. It is evident from the results that there is a considerable impact of conductor configuration on transmission line characteristics. As it can be seen from the results, an increase in spacing leads to higher values of inductance, while an increase in spacing reduces capacitance. When comparing the values of a single conductor with a bundled conductor, there is a marked decrease in inductance and increase in capacitance. Moreover, a double circuit arrangement shows improved characteristics as compared to a single circuit and bundled conductor arrangement. The value of inductance in a double circuit decreases from 0.000626706 Henry to 0.000334949 Henry showing a reduction of about 46.55%, while that of capacitance goes from 1.84912 × 10?? farad to 3.38494 × 10?? farad, signifying an increase of 83.05%. This is mainly due to the electromagnetic coupling effects between conductors of adjacent circuits, reducing the magnetic flux linkages and increasing the effect of electric field. The percentage calculations reveal that inductive effects of bundled conductors decrease to about 43% and capacitive effects go up by about 69.02%, whereas in the case of a double circuit configuration, the reduction in inductance is more than the former (46.55%) and an increase in capacitance is significantly more (83.05%). On the whole, from the analysis and calculations, it is apparent that an efficient conductor configuration like double circuit is highly advantageous in order to improve the efficiency of power transmission, voltage regulation and other power transmission properties. Furthermore, the use of excel modelling for analysing the values of these parameters is very convenient and useful.

References

[1] Modern Power System Analysis by D.P. Kothari and I.J. Nagrath, McGraw Hill Education. [2] Principles of Power System by V.K. Mehta and Rohit Mehta, S. Chand Publications. [3] Manufacturer datasheets for ACSR conductors and overhead transmission line components. [4] Standard electrical engineering lecture materials and reference manuals on inductance and capacitance calculations. [5] International Electrotechnical Commission, International standards for electrical system design. [6] Technical papers and online resources on bundled conductors and transmission line analysis. [7] IEEE, Standards and publications on transmission line design and analysis. [8] International Electrotechnical Commission, International standards for electrical system design.

Copyright

Copyright © 2026 Gohel Arpit Pankajbhai. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.