A Lumped Parameter Thermal Network Model for Dual-Stator Mover-PM Linear-Rotary Generators

Authors

  • Chenxi Li School of Electrical and Information Engineering Zhengzhou University, Zhengzhou 450001, China
  • Rui Nie School of Electrical and Information Engineering Zhengzhou University, Zhengzhou 450001, China
  • Shuai Xu School of Electrical and Information Engineering Zhengzhou University, Zhengzhou 450001, China
  • Yanqi Wei School of Electrical and Information Engineering Zhengzhou University, Zhengzhou 450001, China
  • Peixin Wang School of Electrical and Information Engineering Zhengzhou University, Zhengzhou 450001, China
  • Jikai Si School of Electrical and Information Engineering Zhengzhou University, Zhengzhou 450001, China

DOI:

https://doi.org/10.13052/2026.ACES.J.410604

Keywords:

Dual-stator topology, permanent magnet linear-rotary generator, thermal analysis, lumped- parameter thermal network

Abstract

Mover-permanent magnet linear-rotary generators (MPMLRGs) with dual-stator topology and two degrees of freedom (2-DOF) have attracted growing interest due to their high integration and compactness, enabling coupled linear-rotary motion for direct-drive energy conversion and multifunctional actuation systems. However, the coupled linear-rotary motion and unsymmetric dual-stator topology lead to complex thermal behaviors, and the associated thermal characteristics remain insufficiently investigated compared to electromagnetic studies. In this paper, a lumped-parameter thermal network (LPTN) model is developed for a dual-stator MPMLRG to accurately capture its asymmetric heat transfer and temperature rise under helical motion. A novel approach is proposed to determine the air-gap convective heat transfer coefficients under coupled linear-rotary operation, along with a time-weighted correction method to account for the partial axial overlap of stator-mover surfaces. The thermal model is validated against 3-D thermal finite element analysis (FEA), showing good agreement while significantly reducing computational effort. The results provide useful insights into the thermal management of the dual-stator MPMLRG and establish a foundation for future design optimization and cooling enhancement.

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Author Biographies

Chenxi Li, School of Electrical and Information Engineering Zhengzhou University, Zhengzhou 450001, China

Chenxi Li was born in Sichuan, China, in 2001. She received the B.S. degree in electrical engineering and automation from Henan University of Technology, Zhengzhou, in 2023. She is currently working toward the M.S. degree in the School of Electrical Engineering at Zhengzhou University, Zhengzhou. Her research interests include renewable energy generation technologies and thermal analysis of two-degree-of-freedom motors.

Rui Nie, School of Electrical and Information Engineering Zhengzhou University, Zhengzhou 450001, China

Rui Nie received the B.S. degree in electrical engineering from Henan Polytechnic University, Jiaozuo, China, in 2015, and the Ph.D. degree in electrical engineering from China University of Mining and Technology, Xuzhou, in 2020. She is currently a Research Fellow at Zhengzhou research interests include two-degree-of-freedom machines, linear motor and renewable energy generation technologies.

Shuai Xu, School of Electrical and Information Engineering Zhengzhou University, Zhengzhou 450001, China

Shuai Xu received the B.S. degree in electrical engineering and automation and the Ph.D. degree in electrical engineering from China University of Mining and Technology, Xuzhou, China, in 2014 and 2019, respectively. Since 2021, he has been an Associate Professor at Zhengzhou University. His research interests include motor design and control.

Yanqi Wei, School of Electrical and Information Engineering Zhengzhou University, Zhengzhou 450001, China

Yanqi Wei received the Ph.D. degree in electrical engineering from Zhengzhou University, Zhengzhou, China, in 2024. He is currently a Postdoctoral Researcher with the School of Electrical and Information Zhengzhou University. His research interests include the design, analysis, axial-flux permanent-magnet motors.

Peixin Wang, School of Electrical and Information Engineering Zhengzhou University, Zhengzhou 450001, China

Peixin Wang received the B.S. and M.S. degrees from Henan Polytechnic University, Jiaozuo, China, in 2016 and 2018, respectively, and the Ph.D. degree from Southeast University, Nanjing, in 2022. He is currently a Lecturer at Zhengzhou University. His research interests include air-gap flux modulation theory and the design and analysis of special machines.

Jikai Si, School of Electrical and Information Engineering Zhengzhou University, Zhengzhou 450001, China

Jikai Si received the B.S. degree in electrical engineering and automation from Jiaozuo Institute of Technology, Jiaozuo, China, in 1998, the M.S. degree from Henan Polytechnic University, Jiaozuo, in 2005, and the electrical engineering from China University of Mining and Technology, He is currently a Distinguished Professor at Zhengzhou University. His include the theory and control of special motors.

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Published

2026-06-30

How to Cite

[1]
C. . Li, R. . Nie, S. . Xu, Y. . Wei, P. . Wang, and J. . Si, “A Lumped Parameter Thermal Network Model for Dual-Stator Mover-PM Linear-Rotary Generators”, ACES Journal, vol. 41, no. 06, pp. 524–535, Jun. 2026.

Issue

2026: Vol 41 Iss 6

Section

New Technologies for Electrical Energy Generation & Electric Transportation

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