Latest Trends in the Design of Hairpin Winding Machines for Transport Electrification Purposes

A special issue of Machines (ISSN 2075-1702). This special issue belongs to the section "Machine Design and Theory".

Deadline for manuscript submissions: closed (31 July 2023) | Viewed by 26299

Special Issue Editors


E-Mail Website
Guest Editor
CISE—Electromechatronic Systems Research Centre, University of Beira Interior, Calçada Fonte do Lameiro, P-6201-001 Covilhã, Portugal
Interests: diagnosis and fault tolerance of electrical machines, power electronics and drives
Special Issues, Collections and Topics in MDPI journals

E-Mail Website
Guest Editor
Department of Electrical Machines and Apparatus, Riga Technical University, LV-1658 Riga, Latvia
Interests: electromagnetic design and analysis of electrical machines; development of thermal management system of electrical machines for traction application purposes
Special Issues, Collections and Topics in MDPI journals

E-Mail Website
Guest Editor
Power Electrics, Machines and Control (PEMC) Research Group, The University of Nottingham, Nottingham NG7 2RD, UK
Interests: high-speed machines; novel materials and their applications to electromechanical energy conversion; traction machines
Special Issues, Collections and Topics in MDPI journals

E-Mail Website
Guest Editor

Special Issue Information

Dear Colleagues,

The negative impact of combustion engines on global warming and greenhouse gas emissions enhances the demands for clean and green transportation systems and transport electrification at different levels—for instance, electric vehicles (EVs), electric aviation, and electric trains. The traction motors' demand metrics are mainly concentrated on high power density, high efficiency, cost-effectiveness, and light weight.

There are various ways to enhance the power density of electric motors. The most effective way to achieve high power density is increasing the slot filling factor. The practical option to achieve this target for traction applications is altering the conventional stranded winding with hairpin winding. In recent years, this winding approach has become a popular and common solution for electric motor traction applications, and various automotive manufacturers implement this winding configuration on their electric motors.

This is a call for papers for a Special Issue on the “Latest Trends in the Design of Hairpin Winding Machines for Transport Electrification Purposes”. This Special Issue will provide a forum for researchers and practitioners to exchange their latest theoretical and technological achievements and identify critical issues and challenges for future investigation in the design of electric machine drives using this winding configuration. The submitted papers are expected to raise original ideas and potential contributions to theory and practice. Topics include but are not limited to the following research areas:

  • Various manufacturing techniques of hairpin winding;
  • Design of innovative hairpin winding layouts;
  • Design hairpin winding machines;
  • Thermal management approaches for hairpin winding machines;
  • Accounting and modeling AC winding losses in hairpin winding machines.

Prof. Dr. Antonio J. Marques Cardoso
Dr. Payam Shams Ghahfarokhi
Dr. David Gerada
Prof. Dr. Wen-Ping Cao
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Machines is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2400 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • Hairpin winding
  • Electric motor
  • Transport electrification
  • Design
  • Manufacturing technique
  • Thermal management
  • Modeling
  • AC winding losses

Published Papers (4 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

Jump to: Review

14 pages, 5831 KiB  
Article
Hairpin Windings for Electric Vehicle Motors: Modeling and Investigation of AC Loss-Mitigating Approaches
by Payam Shams Ghahfarokhi, Andrejs Podgornovs, Antonio J. Marques Cardoso, Ants Kallaste, Anouar Belahcen and Toomas Vaimann
Machines 2022, 10(11), 1029; https://doi.org/10.3390/machines10111029 - 4 Nov 2022
Cited by 8 | Viewed by 4255
Abstract
The hairpin winding configuration has been attracting attention as a solution to increase the power density of electric vehicle motors by enhancing the slot-filling factor. However, this winding configuration brings high AC losses during high-speed operation and we require new approaches to tackle [...] Read more.
The hairpin winding configuration has been attracting attention as a solution to increase the power density of electric vehicle motors by enhancing the slot-filling factor. However, this winding configuration brings high AC losses during high-speed operation and we require new approaches to tackle this challenge. This paper considers reducing AC losses by proposing two main methods: correct transposition of conductors in parallel paths, and enhancing the number of conductor layers in a slot. First, the proper connection of conductors in parallel paths is considered, and the essential rules for this purpose are described. Next, the paper uses a numerical approach to deal with the effect of incorrect conductor transposition in winding paths on generating additional AC losses due to circulating currents. Finally, the impact of the number of conductor layers in the mitigation of AC losses is also discussed in detail. According to the results, by increasing the number of layers, ohmic losses in the layer near the slot opening dramatically decrease. For instance, ohmic losses in the layer near the slot opening of the eight-layer setup were 82% less than the two-layer layout. Full article
Show Figures

Figure 1

13 pages, 5852 KiB  
Communication
Investigation of the Temperature Effects on Copper Losses in Hairpin Windings
by Mohammad Soltani, Stefano Nuzzo, Davide Barater and Giovanni Franceschini
Machines 2022, 10(8), 715; https://doi.org/10.3390/machines10080715 - 20 Aug 2022
Cited by 3 | Viewed by 2031
Abstract
Today, an extensive electrification is occurring in all industrial sectors, with a special interest seen in the automotive and aerospace industries. The electric motor, surely, is one of the main actors in this context, and an ever-increasing effort is spent with the aim [...] Read more.
Today, an extensive electrification is occurring in all industrial sectors, with a special interest seen in the automotive and aerospace industries. The electric motor, surely, is one of the main actors in this context, and an ever-increasing effort is spent with the aim of improving its efficiency and torque density. Hairpin windings are one of the recent technologies which are implemented onto the stator of the electric motor. Compared to conventional random windings, it inherently features lower DC resistance, higher fill factor, better thermal performance, improved reliability, and an automated manufacturing process. However, its bottleneck is the high ohmic losses at high-frequency operations due to skin and proximity effects (AC losses), resulting in a negative impact on the temperature map of the machine. Nevertheless, while it is well-known that DC losses increase linearly with the operating temperatures, the AC losses trend needs further insight. This paper demonstrates that operating the machine at higher temperatures could be beneficial for overall efficiency, especially at high-frequency operations. This suggests that a paradigm shift is required for the design of electric motors equipped with hair-pin windings, which should therefore focus on a temperature-oriented approach. In addition, the effect of the rotor topology on AC losses, which is often overlooked, is also considered in this paper. The combination of these effects is used to carry out observations and, eventually, to provide design recommendations. Finite element electromagnetic and thermal evaluations are performed to prove the findings of this research. Full article
Show Figures

Figure 1

13 pages, 71240 KiB  
Article
Mitigation of High-Frequency Eddy Current Losses in Hairpin Winding Machines
by Ahmed Selema, Mohamed N. Ibrahim and Peter Sergeant
Machines 2022, 10(5), 328; https://doi.org/10.3390/machines10050328 - 30 Apr 2022
Cited by 19 | Viewed by 4478
Abstract
In high-speed and high-frequency electric machines, one of the major issues that impacts the performance and capability of a machine is the high-frequency eddy current losses in the windings. This work deals with AC winding losses in flat rectangular conductors. Aiming for eddy [...] Read more.
In high-speed and high-frequency electric machines, one of the major issues that impacts the performance and capability of a machine is the high-frequency eddy current losses in the windings. This work deals with AC winding losses in flat rectangular conductors. Aiming for eddy current loss mitigation, two different materials are investigated and compared for the same winding design, namely copper and aluminum. Using the finite element method (FEM), the conductor loss and current density behavior are simulated at the strand level. Further, in order to verify the simulated losses, the AC losses are measured and compared over a wide range of frequencies. Finally, recommendations are provided based on the obtained measurements to identify the best winding topology that is most suitable for automotive applications. Full article
Show Figures

Figure 1

Review

Jump to: Research

29 pages, 14227 KiB  
Review
Electrical Machines Winding Technology: Latest Advancements for Transportation Electrification
by Ahmed Selema, Mohamed N. Ibrahim and Peter Sergeant
Machines 2022, 10(7), 563; https://doi.org/10.3390/machines10070563 - 12 Jul 2022
Cited by 29 | Viewed by 13022
Abstract
The ever-increasing demand for higher-power dense electrical machines has resulted in different electrical, mechanical, and thermal stresses, which can eventually cause machine failure. For this reason, the management of stresses and losses must be thoughtfully investigated to have a highly reliable electrical machine. [...] Read more.
The ever-increasing demand for higher-power dense electrical machines has resulted in different electrical, mechanical, and thermal stresses, which can eventually cause machine failure. For this reason, the management of stresses and losses must be thoughtfully investigated to have a highly reliable electrical machine. The literature agrees that winding losses are the dominant loss mechanism in many electrical machines. However, statements vary on how to mitigate these losses along with the aforementioned stresses. To avoid winding failure, a study of the various winding topologies would allow for a better consideration of the challenges and limitations in the performance of different electrical machines. To this aim, this paper introduces a comprehensive review for different winding topologies. Many reported cases in the literature are summarized and compared. Moreover, the utilization of additive manufacturing (AM) in the production of the machine windings is presented, showing a high level of maturity of this emerging technology. Finally, different challenges facing the design of machine windings are introduced including the AC high frequency losses, thermal management, mechanical and acoustic problems, insulation aging, automated production, and winding manufacturability. Full article
Show Figures

Figure 1

Back to TopTop