EFFECTS OF ASYMMETRICAL STATOR STRUCTURE ON BLDC MOTOR PERFORMANCE FOR HOUSEHOLD APPLIANCES

Abstract

Brushless direct current motors (BLDCM) have been frequently preferred in the industry, especially in home appliances, due to their advantages such as long life, high efficiency, low maintenance costs and ease of control. In addition to these advantages, the main disadvantages of these motors are known to be high torque ripple and vibration levels. In this study, alternative asymmetric designs are realized in the stator tooth structure of the BLDCM designed for home appliances, and comparative analyses of the effects of the non-uniform air gap caused by the asymmetric tooth structure on the motor performance are presented. Two different asymmetric structures, namely the model with clockwise asymmetric design (CW) and the model with counterclockwise asymmetric design (CCW) in the stator tooth structure, are determined in the stator design. With these alternative designs, improvements are made in terms of torque ripple and cogging torque when compared with the reference motor; notably, the CCW-2 model achieves the lowest ripple at 19.4% compared to 23.1% for the reference motor, and a 42% reduction in cogging torque. The design of the motor models is made in ANSYS EDT program as two dimensional (2D) and analyzed with the Finite Element Method (FEM). In the analysis results, air gap flux density, torque, torque ripple and cogging torque are examined, and the flux density and torque spectrum obtained by Fast Fourier Transform (FFT) are presented comparatively

Keywords

• Electrical Machines
• Brushless DC Motor
• Cogging Torque
• Torque Ripple
• Finite Element Analysis

EV ALETLERİ İÇİN ASİMETRİK STATOR YAPISININ BLDC MOTOR PERFORMANSINA ETKİLERİ

Abstract

Fırçasız doğru akım motorları uzun ömür, yüksek verim, düşük bakım maliyetleri ve kontrol kolaylığı gibi avantajları nedeniyle endüstride özellikle ev aletlerinde sıklıkla tercih edilmektedirler. Bu avantajlarının yanı sıra, moment dalgalanması ve titreşim seviyelerinin yüksek olması bu motorların başlıca dezavantajları olarak bilinmektedir. Bu çalışmada, ev aletleri için tasarlanan fırçasız doğru akım motorun stator diş yapısında alternatif asimetrik tasarımlar gerçekleştirilmiş ve asimetrik diş yapısının neden olduğu düzgün olmayan hava aralığının motor performansı üzerindeki etkilerinin karşılaştırmalı analizleri sunulmuştur. Stator diş yapısında saat yönünde asimetrik tasarıma sahip model (CW) ve saat yönünün tersine asimetrik tasarıma sahip model (CCW) olmak üzere iki farklı asimetrik yapı stator tasarımında belirlenmiştir. Bu alternatif tasarımlarla, referans motorla karşılaştırıldığında moment dalgalanması ve vuruntu momenti açısından iyileştirmeler yapılmaktadır; özellikle CCW-2 modeli, referans motor için %23,1'e kıyasla %19,4 ile en düşük dalgalanmayı ve vuruntu momentinde %42'lik bir azalma elde etmektedir. Motor modellerinin tasarımı ANSYS EDT programında iki boyutlu olarak yapılmış ve Sonlu Elemanlar Yöntemi ile analiz edilmiştir. Analiz sonuçlarında hava aralığı akı yoğunluğu, moment, moment dalgalanması ve vuruntu momenti incelenmiş, Hızlı Fourier Dönüşümü ile elde edilen akı yoğunluğu ve moment spektrumu karşılaştırmalı olarak sunulmuştur.

Keywords

• Elektrik Makinaları
• Fırçasız DC Motor
• Vuruntu Momenti
• Moment Dalgalanması
• Sonlu Elemanlar Analizi

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