Deep-investigated analytical modeling of a surface permanent magnet vernier motor

• Main Authors: Zhu, Jingwei, Zuo, Yuefei, Chen, Hao, Chen, Jiahao, Lee, Christopher Ho Tin
• Other Authors: School of Electrical and Electronic Engineering
• Format: Article
• Language: English
• Published: 2022
• Subjects: Engineering::Electrical and electronic engineering; Analytical Modeling; Finite-Element Analysis
• Online Access: https://hdl.handle.net/10356/160164
• Institution: Nanyang Technological University

Permanent magnet vernier motors possess the advantage of high torque density for high performance applications. However, the low power factor challenge makes it unacceptable for direct-drive applications. A lack of accurate model based on the motor sizing law raises difficulties for machine designers to further conduct research on the performance metrics. This paper presents a deep investigation into the analytical model for surface permanent magnet vernier motors (SPMVMs) to identify an accurate approach to obtain the performance metrics, including torque and power factor. The modeling technique is developed based on conformal mapping with both radial and tangential permeability functions calculated to obtain the magnetic loading considering leakage flux. Then, slotting effect on both air gap flux density and winding function is analyzed to achieve a precise formula for torque and power factor computation. The new modeling technique is applied to integral-slot SPMVMs with various parameters on high power factor and torque density design. Finally, an SPMVM with high torque density and power factor is fabricated to verify the analytical model at the power rating of 0.8 kw and the speed of 500 r/min. The experimental results shows good consistence with the analytical model.