Demagentization Issues in Low Cost Synchronous Machine

The request for high efficiency motor opens the possibility of substituting induction motors with more efficient permanent magnet synchronous motors. For medium and high power, the current ripple causes significant additional losses in the magnet and lamination and correlated demagnetization issues of the rotor permanents magnets due to high temperature. In this paper a new rotor topology is proposed and compared to a traditional surface permanent magnet rotor to reduce the magnet losses and protect them from demagnetization. A reference surface permanent magnet machine is compared with the proposed one in terms of performance and magnet losses. Both analytical and experimental analysis are carried out and shown in the following