1. Design Optimization of an Electric Machine for a 48-V Hybrid Vehicle With Comparison of Rotor Technologies and Pole-Slot Combinations
- Author
-
Chandra S. Namuduri, Lei Hao, Fatemi Alireza, Xiaofeng Yang, Nehl Thomas W, Avoki M. Omekanda, and Gopalakrishnan Suresh
- Subjects
010302 applied physics ,Optimal design ,Electric machine ,Electromagnetics ,business.product_category ,Magnetic reluctance ,Computer science ,020208 electrical & electronic engineering ,02 engineering and technology ,01 natural sciences ,Industrial and Manufacturing Engineering ,Automotive engineering ,Control and Systems Engineering ,Magnet ,0103 physical sciences ,0202 electrical engineering, electronic engineering, information engineering ,Torque ,Torque ripple ,Electrical and Electronic Engineering ,business ,Synchronous motor - Abstract
Through analytical equations followed by a systematic optimization study using high-fidelity finite-element (FE) models, the torque capability of three common synchronous machine technologies—namely, a permanent magnet (PM) synchronous machine (PMSM) with V-shaped rare-earth rotor magnets, a PMSM with deep V-shaped ferrite rotor magnets, and a synchronous reluctance machine (SynRM) with four layers of conforming flux barriers are compared for an application in a 48-V mild hybrid electric car. The optimization of the deep V-shaped ferrite PMSM automatically resulted in a spoke-type PM layout for maximum torque production. Yet, an optimized SynRM with conforming flux barriers was achieved that could produce a higher torque than ferrite PMSM. One machine technology is selected and six variants of it, with two rotor PM layouts each with three alternative pole-slot combinations, are subsequently subjected to a large-scale FE model-based drive-cycle design optimization. Various pole-slot combinations are methodically compared in terms of drive-cycle losses, active material cost, torque ripple, and PM demagnetization level. More than 20 000 designs were analyzed over ten energy-centric torque-speed points to identify an optimal design solution. The results of multiphysics analysis incorporating electromagnetics, computational fluid dynamics, and structural analyses are provided, including a study on three different water jacket concepts. A final design is prototyped and primary experimental results are provided.
- Published
- 2020