Blade Designs, Generator Systems, and Contra-Rotating Architectures in Vertical Axis Wind Turbines: A Review

Abstract

Abstract: This review re-examines the vertical-axis wind turbine (VAWT) literature through three coupled design layers: blade and rotor design, generator systems, and contra-rotating or multi-rotor configurations. Drawing on more than 130 peer-reviewed studies, the paper synthesizes findings on Savonius, Darrieus/H-rotor and hybrid rotors; direct-drive permanent-magnet synchronous generators, axial-flux machines and alternative electromechanical topologies; and coaxial, twin and clustered VAWT layouts. The review shows that airfoil selection, pitch, solidity, aspect ratio, helical or twisted geometry and self-starting strategies affect not only the peak power coefficient, but also static torque, torque ripple and structural loading. On the electrical side, direct-drive PMSG and axial-flux solutions are attractive for low-speed operation, yet system performance depends on the coupled rotor torque curve, starting strategy, load matching and power electronics. For contra-rotating and clustered layouts, performance gains are conditional on spacing, rotational direction, inflow angle and power-take-off architecture. The main conclusion is that VAWT performance cannot be explained by single-component optimization; future work should address aerodynamic, electrical, structural, reliability and farm-density metrics within validated multi-objective design frameworks.

Keywords

• vertical axis wind turbine
• VAWT
• blade design
• Savonius
• Darrieus
• generator
• PMSG
• axial-flux
• contra-rotating turbine
• ; aero-electric co-design

Dikey Eksenli Rüzgâr Türbinlerinde Kanat Tasarımları, Generatör Sistemleri ve Kontra-Dönüşlü Yapılar: Bir Derleme

Abstract

Özet: Bu derleme, dikey eksenli rüzgâr türbinleri (DERT/VAWT) literatürünü üç bağlı tasarım katmanı üzerinden yeniden değerlendirmektedir: kanat ve rotor tasarımları, generatör sistemleri ve kontra-dönüşlü/çok rotorlu konfigürasyonlar. Çalışmada 130’dan fazla hakemli yayından oluşan bir korpus kullanılarak Savonius, Darrieus/H-rotor ve hibrit rotor aileleri; direct-drive kalıcı mıknatıslı senkron generatörler, axial-flux makineler ve alternatif elektromekanik topolojiler; ayrıca eş-eksenli, twin ve cluster DERT yerleşimleri birlikte tartışılmıştır. Bulgular; airfoil seçimi, pitch, solidity, aspect ratio, helisel veya twisted geometri ve öz-yolverme stratejilerinin yalnızca tepe güç katsayısını değil, statik momenti, tork dalgalanmasını ve yapısal yük spektrumunu da belirlediğini göstermektedir. Elektriksel tarafta direct-drive PMSG ve axial-flux çözümler düşük devirli çalışma açısından güçlü adaylar olsa da gerçek sistem performansı rotor moment eğrisi, başlatma stratejisi, yük eşleştirmesi ve güç elektroniğiyle birlikte şekillenmektedir. Kontra-dönüşlü ve cluster yapılarda ise performans kazanımları spacing, rotational direction, inflow angle ve güç alma mimarisinin ortak optimizasyonuna bağlıdır. Derlemenin temel sonucu, DERT performansının tek bileşenli optimizasyonla açıklanamayacağı; gelecek çalışmaların aerodinamik, elektriksel, yapısal, güvenilirlik ve farm güç yoğunluğu metriklerini doğrulanmış çok amaçlı tasarım çerçeveleri içinde birlikte ele alması gerektiğidir.

Keywords

• dikey eksenli rüzgâr türbini
• VAWT
• kanat tasarımı
• Savonius
• Darrieus
• generatör
• PMSG
• eksenel akı
• kontra-dönüşlü türbin
• aero-elektrik ortak tasarım

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