A model to predict current distributions in bundled cables for electric glass melters

A model for predicting the current distribution in high-current cables that are constructed from bundles of parallel conductors (strands) is presented. These cables are typically used in electric glass melters to interconnect the power transformers and the melter secondary bus installations. Due to the phenomenon known as the skin effect, the magnetic field forces inside the bundled cable will tend to drive the current toward the outermost strands. The proposed model is developed by starting from the fundamentals of the skin effect phenomenon for solid conductors and then extending the concept for bundled cables. The model has also been coded in a simple FORTRAN computer program. Results obtained using the proposed model for a variety of cable bundling configurations are presented for demonstration purposes. These results show that currents in the outermost layers of bundled cables can exceed those of the innermost layers by a factor of four or more, depending on the total cable size