Air Gap Field Comparison of Hybrid and Electrical Excited Synchronous Machines Without Rare Earth Magnets for Use in Road Vehicles

The individual mobility is changing from fuel to battery electric drive. During the run-up of the technology the pollution and the accessibility of resources get into focus. The object of this paper is a comparison of two hybrid excited synchronous machines (HESM). To support the environmental goals rare earth free ferrite magnets are used. In a first step an analytical basic simulation of the air gap field was done. There an approximation of potential of the HESM with magnets in tooth and HESM tangential/radial flux (HESM TR) was cal-culated. Second step is the measurement of the magnetic field in a test pattern. A changeable rotor enables the measurement of the HESM and an electrical excited synchronous machine (EESM) in one stator.