Synchronous Reluctance Machines with and without Ferrite Assistance for Lifting Systems

This paper deals with the comparative design and testing of synchronous reluctance machines with and without the addition of ferrite magnets for lifting applications. First, an efficient design process is proposed and showcased for both machine types. Given the application specifications of peak torque and maximum speed, the process permits quickly determining the cross-section of the motors, as well as the corresponding inverter current rating. Once the final design is defined, the optimal steps-kewing angle is defined and applied in seamless computational time; for the ferrite-assisted machine, the demagnetization limit is assessed. After comparing the two designs in terms of key performance indexes and expected cost of production, the synchronous reluctance machine prototype was built and tested. The experimental tests include the measurement of the flux linkage maps and tests under load with related thermal measurements; the experimental findings are compared with the model results demonstrating an excellent match.