Motor Integrated Rotating Permanent Magnet based Electrodynamic Suspension Device: Part II - Investigation of Coupled Topology

This article discusses the operational aspects of a 12-slot/10-pole, coupled motor integrated electrodynamic wheel (MIEDW), proposed in Part-I of the two companion articles. MIEDW is a compact arrangement for realizing contact-less force/torque transmission using principle of electrodynamic suspension (EDS). In this machine, the EDS and the integrated motor components are magnetically coupled. Due to this, EDS conditions affect the motor operating conditions. The motor airgap field distribution becomes asymmetric. This results in unbalanced flux-linkages among the phases of the motor. This unbalance is investigated in detail using 2D finite element analysis, and its effect on the terminal quantities is presented. A brief discussion on practical realization of the MIEDW is provided, corroborated with structure simulations. It is found that the rotor having cage structure to retain the magnets is electromagnetically and structurally superior to the rotor with shell type structure, for the same physical clearance. Using cage rotor structure with block-shaped magnets, a proof-of-concept prototype is developed to verify the operation of the proposed topology and validate the finite element analysis simulation models used in both the articles. Additionally, the experimental verification of the asymmetric airgap field distribution in the presence of plate is also provided.