Magnetic Field Analysis in Shell-Like Spherical Induction Machines with Zenithal Traveling Waves

In this paper, a magnetic field analysis is done for spherical shell-like induction machines with a zenithal progressive magnetic traveling wave, using an analytical model in spherical coordinates. These analytical models have major importance in the simulation, project, and preliminary optimization of devices due to its analytical solutions and physical insight. The magnetic field analysis is made for a shell-like induction machine for the study of its electromagnetic and mechanical quantities, as the magnetic field, induced currents, and electromagnetic torque. The developed model is validated, first with a set of generic windings distributions using the results of a commercial finite element analysis (FEA) tool and, second, validated by comparing with the results from the shell-like induction machine prototype. The results obtained from the analytical model are very close to the ones obtained by the FEA tool and from the prototype tests.