Analysis of formulas to calculate the AC resistance of different conductors’ configurations

•Skin and proximity can notoriously affect the AC resistance in electrical conductors.•The AC resistance affects power loss and conductors ampacity.•The accuracy of some formulas to evaluate the AC resistance of conductors is assessed.•Comparisons with experimental and FEM simulations results are done.•Results show that FEM simulation results are very accurate and more general.

Skin and proximity effects in single- or multi-conductor systems can notoriously affect the AC resistance in conductors intended for electrical power transmission and distribution systems and for electronic devices. This increase of the AC resistance raises power loss and limits the conductors’ current-carrying capacity, being an important design parameter. There are some internationally recognized exact and approximated formulas to calculate the AC resistance of conductors, whose accuracy and applicability is evaluated in this paper. However, since these formulas can be applied under a wide range of configurations and operating conditions, it is necessary to evaluate the applicability of these models. This is done by comparing the results that they provide with experimental data and finite element method (FEM) simulation results. The results provided show that FEM results are very accurate and more general than those provided by the formulas, since FEM models can be applied to a wide range of conductors’ configurations and electrical frequencies.