Analysis and performance of eddy-current brakes with ferromagnetic loss drums. Part 1: Nonsalient-pole brakes

A simple graphical method is presented for predetermining the performance of an eddy-current brake with a ferromagnetic loss drum when the B/H curve of the latter is expressed in the form B = ??H1??2/n. The method also takes into account the saturation of the pole structure, if present. In the absence of pole saturation, normalised force/speed and flux/speed characteristics are obtained. It is shown that, to obtain the highest brake force, the B/H curve of the drum material should be limiting nonlinear. The analysis, based on fundamental components of the field quantities and uniform airgap permeance, is found to give satisfactory results when applied to nonsalient-pole brakes. (See also companion paper: IEE Proc. B, Electr. Power Appl., 1982, 129, (3), pp. 132??142.)