Finding Electromagnetic Loads and Magnetic-Field Factors in Design of Integrated Brushless Excitation DC Generator

The paper covers the design of an integrated brushless excitation direct-current generator (IBEDCG), where the exciter and the main generator are located in the same magnetic system. When sizing the active part of such machines, one must choose and distribute the electromagnetic loads: magnetic flux density in the main-generator and exciter gap, and stator/rotor line current density. The research team investigated the magnetic-field factors (the estimated pole overlap factor, the form factor of the excitation flux and the EMF form factor) as a function of the exciter excitation winding design and magnetic-system saturation. The article compares the results of the FE simulation and analytical calculation of these coefficients. The suggestions on choosing the electromagnetic loads ratio of the exciter and the main generator are given. The paper provides specifications of a prototype generator for a special vehicle on tracks.