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Journals / Erzincan Üniversitesi Fen Bilimleri Enstitüsü Dergisi / 2026 / Cilt: 19 Sayı: 2

Performance Comparison of a Yokeless and Segmented Armature Type Axial Flux Induction Motor in Terms of Rotor Bar Number, Material, and Operating Speed

Boyunduruksuz ve Segmentli Armatür tipi Eksenel Akılı Asenkron Motorun, Rotor Bar Sayısı, Malzemesi ve Çalışma Hızı Kapsamında Performans Karşılaştırması

Harun Aslaner(TOKAT GAZIOSMANPASA UNIVERSITY, FACULTY OF ENGINEERING)0000-0002-4716-3064
Mehmet Akar(TOKAT GAZIOSMANPASA UNIVERSITY, FACULTY OF ENGINEERING)0000-0003-0164-1451
Pages
158–181
Publication Date
2026-08-31
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AI Summary & Key Takeaways

AI Insight
⚡ TL;DR(Too Long; Didn't Read)

The results indicate that, when copper is used as the rotor bar material, the 41 bar configuration is the most suitable choice across all three operating speeds.

📌 3 Key Takeaways

🎯
Objective & Hypothesis:This study provides a detailed examination of the Yokeless and Segmented Armature type (YASA) Axial Flux Induction Motor (AFIM) structure, which is scarcely addressed in the literature.
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Key Findings & Data:The main objective of the study is to systematically compare the effects of rotor bar number, rotor bar material, and operating speed on motor performance, and to provide guidance for future studies.
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Conclusion & Impact:The results indicate that, when copper is used as the rotor bar material, the 41 bar configuration is the most suitable choice across all three operating speeds.
🔬Design:Modeling & Simulation
📍Scope:2000 Verileri
⚙️Variables:Boyunduruksuz ve Segmentli · Eksenel Akılı Asenkron Motor · Sonlu Elemanlar Yöntemi

Abstract

This study provides a detailed examination of the Yokeless and Segmented Armature type (YASA) Axial Flux Induction Motor (AFIM) structure, which is scarcely addressed in the literature. In the study, a YASA-type AFIM with a double-rotor architecture was analyzed using Finite Element Methods (FEM) for five different rotor bar numbers and three operating speeds, while keeping the stator structure constant and employing both aluminum and copper rotor bar materials. The main objective of the study is to systematically compare the effects of rotor bar number, rotor bar material, and operating speed on motor performance, and to provide guidance for future studies. The motor, featuring 6 poles and 9 stator slots, was tested for 29, 31, 35, 37, and 41 rotor bars using both aluminum and copper as rotor bar materials. Analyses at operating speeds of 1000, 2000, and 3000 rpm compared torque, torque ripple, efficiency, and losses. To enable the interpretation of multi-criteria optimization, an Optimal Motor Configuration for this study was determined using a Normalized Performance Index. The results indicate that, when copper is used as the rotor bar material, the 41 bar configuration is the most suitable choice across all three operating speeds. When aluminum is used, the 29 bar configuration is optimal at 1000 rpm, whereas the 41 bar configuration is optimal at 2000 and 3000 rpm. The obtained data provide a foundation for needs-based parameter optimization in future YASA-type AFIM designs, facilitating further research in this field.

Özet

Bu çalışma literatürde oldukça sınırlı sayıda yer bulan Boyunduruksuz ve Segmentli Armatür tipi (YASA) Eksenel Akılı Asenkron Motor (EAASM) yapısını detaylıca ele almaktadır. Çalışmada, YASA tipi çift rotor mimarisine sahip EAASM, stator yapısı sabit tutularak; alüminyum ve bakır rotor bar malzemesi kullanılarak 5 farklı rotor bar sayısı için 3 farklı çalışma hızında Sonlu Eleman Yöntemleri (SEY) ile analiz edilmiştir. Çalışmanın temel amacı; rotor bar sayısı, rotor bar malzemesi ve çalışma hızı parametrelerinin motor performansı üzerindeki etkilerini sistematik olarak kıyaslamak ve bundan sonra yapılacak çalışmalara da kolaylık sağlamaktır. 6 kutup, 9 stator oluğuna sahip motor 29,31,35,37 ve 41 rotor bar sayısı için hem alüminyum hem de bakır rotor bar malzemesi kullanılarak sınanmıştır. 1000,2000 ve 3000 rpm çalışma hızlarının ele alındığı analizlerde tork, tork dalgalanması, verimlilik ve kayıplar kıyaslanmış olup çok kriterli optimizasyonun yorumlanabilmesi adına Normalize Performans İndeksi ile söz konusu çalışma için optimal motor yapısı belirlenmiştir. Analiz sonuçları rotor bar malzemesi olarak bakır kullanılması durumunda 41 bar yapısının 3 farklı çalışma hızında da en uygun seçim olduğunu, alüminyum kullanılması durumunda ise 1000 rpm için 29 bar yapısının, 2000 ve 3000 rpm hızlarında ise 41 bar konfigürasyonunun optimum rotor oluk sayısı olduğunu göstermektedir. Elde edilen veriler, YASA tipi EAASM tasarımı için yapılacak olan ileriki çalışmalar adına ihtiyaç odaklı parametre optimizasyonuna olanak sağlarken, bu kapsamda araştırmacılara kolaylık sağlayacağı öngörülmektedir.

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Cite This Article

Aslaner, H., Akar, M. (2026). Performance Comparison of a Yokeless and Segmented Armature Type Axial Flux Induction Motor in Terms of Rotor Bar Number, Material, and Operating Speed. Erzincan Üniversitesi Fen Bilimleri Enstitüsü Dergisi, Cilt: 19 Sayı: 2, 158–181. https://doi.org/10.18185/erzifbed.1914062

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