Sabit Mıknatıslı Senkron Makinelerde Demanyetizasyon: Modelleme, Teşhis ve Gelecek Yönelimler

Öz

Elektrikli araç ve yenilenebilir enerji sistemlerinde Sabit Mıknatıslı Senkron Makineler (SMSM), yüksek tork yoğunluğu ve üstün verimlilikleri nedeniyle yaygın olarak kullanılmaktadır. Bu makinelerde meydana gelen arızalar, özellikle elektrikli araç tahrik sistemlerinde ve rüzgâr türbinlerinde performans kaybı, güvenirlik sorunları ve ek bakım maliyetlerine yol açmaktadır. Sürekli değişen yük, hız ve sıcaklık koşulları altında SMSM’lerin arıza eğilimi artmakta olup demanyetizasyon, rotor mıknatıslarının kalıcı manyetik özelliklerini kaybetmesi nedeniyle en kritik arızalardan biri olarak kabul edilmektedir. Demanyetizasyon, manyetik çevrimin kararlılığını bozarak akı dağılımının değişmesine, moment dalgalanmalarının artmasına, harmonik bozulmalara ve ısıl kararsızlığa neden olur. Düzensiz demanyetizasyon ise rotor çevresinde asimetri oluşturarak titreşim ve akustik gürültüyü yükseltir. Bu çalışmada demanyetizasyon arızaları bütüncül olarak ele alınmış; manyetik bozulma mekanizmaları ile teşhis göstergeleri arasındaki ilişki detaylandırılmıştır. Mıknatıs malzemesi özellikleri, knee bölgesi davranışı ve termal–manyetik etkileşimler değerlendirilmiş; B–H eğrisine dayalı analitik modellere ek olarak farklı arıza seviyelerinin manyetik tepkileri Sonlu Elemanlar Analizi (SEA) ile incelenmiştir. SEA sonuçları üzerinden akı zayıflaması, tork üretimi, zıt elektromotor kuvvet ve alan yoğunluğu değişimleri nicel olarak karşılaştırılmıştır. Ayrıca sinyal işleme, gözlemci tabanlı ve makine öğrenmesi destekli teşhis yöntemleri performans, gürültü dayanımı, sensör gereksinimi ve gerçek zamanlı uygulanabilirlik açısından karşılaştırılmıştır. Bu çalışma, elektrikli araç ve rüzgâr enerjisi uygulamaları için kapsamlı bir referans çerçeve sunmakta ve hibrit teşhis yaklaşımlarının gelecekteki araştırmalar için sunduğu potansiyeli tartışmaktadır.

Anahtar Kelimeler

• Sabit Mıknatıslı Senkron Makine
• demanyetizasyon arızası
• arıza tespiti
• arıza modellenmesi
• arıza teşhis yöntemleri

Demagnetization in Permanent Magnet Synchronous Machines: Modeling, Diagnosis, and Future Directions

Öz

Permanent Magnet Synchronous Machines (PMSMs) are widely used in electric vehicles and renewable energy systems due to their high torque density and superior efficiency. Faults occurring in these machines may lead to performance loss, reliability problems, and additional maintenance costs, especially in electric vehicle drive systems and wind turbines. Under continuously changing load, speed, and temperature conditions, the tendency of PMSMs to experience faults increases, and demagnetization is considered one of the most critical faults because rotor magnets lose their permanent magnetic properties. Demagnetization disrupts the stability of the magnetic circuit, causing changes in flux distribution, increased torque ripple, harmonic distortion, and thermal instability. Irregular demagnetization also creates asymmetry around the rotor, increasing vibration and acoustic noise. In this study, demagnetization faults are examined in a holistic manner, and the relationship between magnetic degradation mechanisms and diagnostic indicators is detailed. Magnet material properties, knee-region behavior, and thermo-magnetic interactions are evaluated, and in addition to analytical models based on the B–H curve, the magnetic responses under different fault levels are investigated using Finite Element Analysis (FEA). Through FEA results, flux weakening, torque production, back-EMF, and air-gap flux density variations are quantitatively compared. In addition, diagnostic methods based on signal processing, observer structures, and machine-learning-supported approaches are compared in terms of performance, noise robustness, sensor requirements, and real-time applicability. This study provides a comprehensive reference framework for applications in electric vehicles and wind energy systems and discusses the potential offered by hybrid diagnostic approaches for future research directions.  

Anahtar Kelimeler

• Permanent Magnet Synchronous Machine
• demagnetization faults
• fault diagnosis
• fault modeling
• fault diagnosis methods

Kaynakça

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