INVESTIGATION OF THE EFFECTS OF MAGNET GEOMETRY ON MOTOR PERFORMANCE AND COST IN PERMANENT MAGNET SYNCHRONOUS MOTORS USED IN DIRECT DRIVE ELEVATOR SYSTEMS

Abstract

Direct drive systems eliminate the need for drivetrain such as gearboxes to provide higher efficiency and a more compact structure. In this study, magnet geometry of surface mounted permanent magnet synchronous motors used in direct drive elevator applications was changed and its effects on motor performance and total active material cost were investigated. As is known, the cost of magnets used in electric motors has a significant share on total motor cost. Consequently, a 5.5 kW surface mounted permanent magnet synchronous motor has been designed, analyzed and its parameters are presented. For the motor that passes the first design phase, the parameters that constitute the magnet geometry given as pole arc/pole pitch ratio, pole offset and magnet thickness values determined as variable and parametric solutions were implemented. As a result of the analyses, motor efficiency, cogging torque, total magnet weight and maximum output power values were obtained and compared. In addition, the total costs of the motors were compared for designs that aim different design criteria. Thus, the initial design was optimized by obtaining the magnet geometry and motor design that provides an optimal equilibrium between motor efficiency and cost. As a result, 30% lower cost was obtained. However, while the maximum efficiency is obtained as approximately 91%, the optimized design offers an acceptable efficiency of about 88%.

Keywords

• Elevator,Direct Drive,Permanent Magnet,Synchronous Motor,Cost

DOĞRUDAN TAHRİKLİ ASANSÖR SİSTEMLERİNDE KULLANILAN SABİT MIKNATISLI SENKRON MOTORLARDA MIKNATIS GEOMETRİSİNİN MOTOR PERFORMANSI VE MALİYETİ ÜZERİNDEKİ ETKİLERİNİN İNCELENMESİ

Abstract

Doğrudan tahrikli sistemler dişli kutusu gibi aktarma organlarına olan ihtiyacı ortadan kaldırarak daha yüksek verimlilik ve daha küçük bir yapı sunmaktadırlar. Bu çalışmada, doğrudan tahrikli asansör uygulamalarında kullanılan sabit mıknatıslı senkron motorlarda mıknatıs geometrisi değiştirilerek motor performansı ve maliyeti üzerindeki etkileri incelenmiştir. Motorlarda kullanılan mıknatıslara ait maliyet, toplam motor maliyeti üzerinde önemli bir paya sahiptir. Bu sebeple öncelikle 5,5 kW gücünde yüzey yerleştirmeli bir sabit mıknatıslı senkron motor tasarlanıp analiz edilerek parametreleri sunulmuştur. İlk tasarım aşamasını geçen motorda mıknatıs geometrisini belirleyen kutup yayı/kutup adımı oranı, kutup çıkıntı kaçıklığı (ofseti) ve mıknatıs kalınlığı değerleri değişken olarak tanımlanmış ve parametrik çözümler gerçekleştirilmiştir. Analizler sonucunda motor verimi, vuruntu momenti, toplam mıknatıs ağırlığı ve maksimum çıkış gücü değerleri elde edilerek karşılaştırılmıştır. Ayrıca farklı kriterleri amaçlayan tasarımlar için motorların toplam maliyetleri karşılaştırılmıştır. Böylelikle motor verimi ve maliyeti arasında en iyi dengeyi sunan mıknatıs geometrisi ve motor tasarımı elde edilerek başlangıç tasarımı iyileştirilmiş ve %30 daha düşük maliyet elde edilmiştir. Bununla birlikte maksimum verimlik yaklaşık olarak %91 olarak elde edilirken, dengeli tasarım yaklaşık olarak %88 değerinde kabul edilebilir bir verimlilik sunmaktadır. 

Keywords

• Asansör,Doğrudan Tahrik,Sabit Mıknatıs,Senkron Motor,Maliyet

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