Mechanical and Electromagnetic Analysis of High Speed Motor/Generator for Electric Turbo Compounding System

Bongseok Choi, Donghoon Jung, Jaek wang Lee, Ju Lee*
Department of Electrical Engineering, Hanyang University, Seoul, Korea



Recently, environment-friendly technologies are being introduced as global warming is rapidly progressing. One of the effective way to reduce the problem, Electric Turbo Compounding System has been researched globally. With this system, about 30% exhaust gas can be recycled as a power source. Therefore, this system is effective for engine systems with purposes such as downsizing and increasing efficiency of the system.

Objective & Method:

Surface mounted Permanent Magnet Motor is applied to this system due to its high efficiency, power density, small size, and low weight. However, during high speed operation, a retaining sleeve is essential in rotor such as Inconel 718 to satisfy a mechanical safety factor of the rotor. In this paper, through basic theory, the sleeve thickness is predicted according to the permanent magnet dimension and minimum sleeve thickness is determined satisfying mechanical safety factor by mechanical analysis. Furthermore, by electromagnetic analysis output characteristics according to the permanent magnet dimension having same constraints such as volume, current density, current and flux distribution are compared.

Result & Conclusion:

Based on the results of the electromagnetic analysis and mechanical analysis, the appropriate ratio of electric and magnetic loading is determined with equivalent constraint condition. Consequently, only model 2 satisfies the requirement at rated and maximum speed within the current limit.

Keywords: Multiphysics, Surface mounted Permanent magnet Motor (SPM), High speed, Turbo charger, Safety factor, Inconel 718.

Abstract Information

Identifiers and Pagination:

Year: 2018
Volume: 12
Publisher Item Identifier: EA-TOEEJ-2018-9

Article History:

Received Date: 31/3/2018
Revision Received Date: 26/6/2018
Acceptance Date: 20/7/2018
Electronic publication date: 11/10/2018
Collection year: 2018

© 2018 Choi et al.

open-access license: This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International Public License (CC-BY 4.0), a copy of which is available at: This license permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

* Address correspondence to this author at the Department of Electrical Engineering, Hanyang University, Seoul, Korea; Tel: +822-2220-0342, Fax: +822-2295-7111; E-mail: