Multiple Layer Series Connected Winding Design for Minimum Losses

The classical one dimensional magnetic field and eddy current distribution ("proximity effect") within a series connected multiple layer coil is reexamined with regard to power losses withinthe windings. When the lengthand number of layers ina coilare fixed, the power dissipation within each layer can be minimized by choosing a specific radial thickness for each layer. Above or below this thickness, the losses within the winding increase. The conductor thickness which results in minimum dissipation depends on the relative position of the layer. When compared to a design having a constant thickness for each layer (chosen for minimum total dissipation), it is found that substantial savings in power consumption can be realized by employing a variable thickness of conductor. The one dimensional solution in cylindrical coordinates for the eddy current and skin effect in amultiple layer series connected coil is alsopresented. By solving the problem n cylindrical coordinates, the effect of curvature on the power consumption within each layer is apparent. This analysis should have application to the design of power transformers, armature windings, and inductors for power transmission lines.