Dissymmetry in D-C Rotating Electric Machines

A new technique for detecting dissymmetries built or developed in rotating electric machines is introduced. It is presented with the intent of interesting machine manufacturers to investigate the ideas developed and the degree of practical advances that may be realized by measuring, analyzing, and minimizing detrimental nonuniformities found in such rotating devices. The method promises a simple and more accurate test and final machine adjustment tool. Heretofore unsuspected causes of harmful effects are shown to be mechanical, magnetic, and electrical machine unbalances. The internal electric transients revealed throw new light on machine sizes, efficiencies, radio interference, carbon brush evaluating techniques, and application, as well as on the commutation phenomenon itself. It indicates that exact duplicate machines are rare accidents. The easing of present operating conditions for carbon brushes and extended life for the versatile d-c system are envisioned.