Modular e-Torque System for Small Engines via Triple Energy Harvesting: Thermoelectric, Braking, and Airflow Integration

Öz

This paper proposes a modular e-Torque architecture designed for small-displacement internal combustion engines (1.5 L) to provide hybrid-like torque assistance with minimal cost and system complexity. The proposed system integrates three complementary energy-harvesting sources: regenerative braking, thermoelectric generators (TEGs), and an air-driven turbine. The recovered energy is stored in a centralized battery and managed through a dedicated power-management framework connected to a Motor Generator Unit (MGU) that supplies torque support during acceleration and load-demand conditions. A hierarchical control strategy prioritizes regenerative braking due to its higher instantaneous energy recovery, followed by continuous thermoelectric generation, while the air-driven turbine operates as an auxiliary source to maintain battery readiness. Analytical modeling under typical urban driving conditions indicates that the integrated system can recover approximately 65 W of electrical power (TEG ≈ 30 W, regenerative ≈ 20 W, turbine ≈ 15 W). This recovered energy can assist the MGU in providing torque support while reducing alternator load and mechanical braking demand. The proposed architecture demonstrates a compact and scalable solution for enhancing energy efficiency in small-engine vehicles by utilizing otherwise wasted thermal and aerodynamic energy. Future work will focus on simulation validation, prototype development, and advanced control optimization.  

Anahtar Kelimeler

• Modular e-Torque system
• Small-displacement engines;
• Regenerative braking;
• Thermoelectric generators;
• Airflow energy harvesting;

Modüler e-Tork Sistemi için Üçlü Enerji Toplama Yoluyla Küçük Motorlarda Termoelektrik, Fren ve Hava Akışı Entegrasyonu

Öz

Bu çalışma, küçük hacimli içten yanmalı motorlar (1,5 L) için düşük kütle, maliyet ve karmaşıklıkla hibrit benzeri tork desteği sağlayan modüler bir e-Tork mimarisi sunmaktadır. Sistem; rejeneratif frenleme, termoelektrik jeneratörler (TEG’ler) ve hava tahrikli bir türbin olmak üzere üç enerji hasadı kaynağını merkezi bir enerji depolama ve güç yönetimi yapısına entegre etmektedir. Kayış tahrikli bir Motor-Jeneratör Ünitesi (MGU), depolanan enerjiyi ani hızlanma ve yokuş tırmanma sırasında hedefli destek sağlamak için kullanmaktadır. Hiyerarşik bir kontrolör, öncelikle yüksek verimli rejeneratif frenlemeye, ardından sürekli TEG çıkışına öncelik vermekte ve batarya hazır durumunu korumak amacıyla türbini koşullu olarak devreye almaktadır. Özel dönüştürücüler gerilimi düzenlemekte, uygun durumlarda maksimum güç noktası takibini yapmakta ve merkezi bir DC bara üzerinde çift yönlü enerji akışını mümkün kılmaktadır. Kentsel sürüş çevrimleri için yapılan analitik modelleme, ortalama yaklaşık 65 W’lık birleşik bir enerji geri kazanımına işaret etmektedir (TEG ≈ 30 W, rejeneratif frenleme ≈ 20 W, türbin ≈ 15 W). Bu durum, kompakt bir MGU aracılığıyla tork artışlarını desteklerken alternatör yükünü ve mekanik fren aşınmasını azaltmaktadır. Bulanık kurallar veya eşik değerler ile uygulanan üst seviye kontrol mantığı, anlık güç talebi, şarj durumu ve termal sınırlar doğrultusunda enerji kaynaklarını koordine etmektedir. Bu yaklaşım, normalde kaybedilecek olan ısı ve dinamik basınç enerjisinin geri kazanılmasıyla araç üzerindeki enerji bütçesini genişletmekte ve büyük ölçekli motor yeniden yapılandırmalarına gerek kalmadan sürüş kabiliyetini ve yakıt ekonomisini iyileştirmektedir. Çalışma; küçük motor platformları için bileşen rolleri, kontrol öncelikleri ve uygulanabilirlik sınırlarını ortaya koymakta; etkin TEG termal arayüzleri, aerodinamik türbin tasarımı ve DC bara üzerindeki koruyucu işlevler gibi entegrasyon gereksinimlerine dikkat çekmektedir. Genel olarak önerilen e-Tork sistemi, maliyet hassasiyeti yüksek araçlarda hibrit benzeri faydalara ulaşmak için kompakt ve bütünleşik bir yol sunmaktadır. Gelecek çalışmalar, kavramın simülasyon, donanım prototipleme ve kontrol iyileştirmeleri yoluyla doğrulanmasını amaçlamaktadır.

Anahtar Kelimeler

• Modüler e-Tork sistemi
• Küçük hacimli motorlar
• Rejeneratif frenleme
• ermoelektrik jeneratörler;
• Hava akışından enerji hasadı

Kaynakça

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