Yuichi Shibukawa, Nissan Motor Co., Ltd.
This paper proposes a new rotor design for flux-intensifying interior permanent magnet synchronous machine (FI-IPM SM) which has similar torque-speed and power capabilities to a traditional flux-weakening IPM SM (FW-IPM SM). Design steps for the rotor structure of the new machine are laid out and discussed to emphasize key designing challenges. The proposed FI-IPM SM and a FW-IPM SM with similar torque-speed capability, are made to evaluate performances in power conversion as well as self-sensing capability at very low speed. Finite-element analysis (FEA) is used
to evaluate the machine performances. The proposed FI-IPM SM shows less variation in the saliency when the machine is loaded, leading to a possibility of better self-sensing performance at very low speed as compared to the traditional FW-IPM SM. Experimental results on the self-sensing performance of these two machines are also shown for verification.