Modeling and Performance Analysis of Continuously Variable Series Reactors (CVSR) for Congestion Management in Meshed Distribution Networks

Abstract

Distribution systems, particularly in densely loaded urban areas, frequently experience transformer overloading during peak consumption hours. Rather than resorting to costly infrastructure reinforcement or complex Flexible AC Transmission Systems (FACTS), this paper proposes a cost-effective optimization and control approach utilizing a Continuously Variable Series Reactor (CVSR). Unlike FACTS devices that rely on expensive power electronics, the CVSR capitalizes on magnetic core saturation to regulate reactance, offering a robust solution at a fraction of the cost (~$10/kVAr). The CVSR regulates the reactance on the primary side of the transformer via magnetic core saturation to control power distribution among transformers. In this study, the steady-state framework of the CVSR is derived and integrated into power flow formulations. The proposed model is validated using a two-parallel transformer system and tested on the heavily meshed IEEE 342-Node Low Voltage Networked Test System (LVNTS). Simulation results demonstrate the CVSR effectively relieves transformer overloading by redistributing power flow, thereby enhancing system flexibility and allowing utilities to avoid or defer extensive grid upgrades.

Keywords

• congestion management
• power flow control
• distribution systems
• load shifting
• meshed grids

Örgülü Dağıtım Şebekelerinde Tıkanıklık Yönetimi İçin Sürekli Değişken Seri Reaktörlerin (CVSR) Modellenmesi ve Performans Analizi

Abstract

Özellikle yoğun yüklü kentsel alanlardaki dağıtım sistemleri, en yüksek tüketim saatlerinde sıklıkla transformatör aşırı yüklenmesi yaşamaktadır. Bu çalışma, yüksek maliyetli altyapı güçlendirme yatırımlarına veya karmaşık Esnek Alternatif Akım İletim Sistemlerine (FACTS) başvurmak yerine, Sürekli Değişken Seri Reaktör (CVSR) kullanımına dayalı, maliyet açısından etkin bir optimizasyon ve kontrol yaklaşımı önermektedir. Pahalı güç elektroniği bileşenlerine dayalı FACTS cihazlarının aksine CVSR, reaktans ayarını manyetik çekirdek doyumu prensibiyle gerçekleştirmekte; mevcut çözümlerin maliyetinin çok altında bir bedelle (~10 $/kVAr) sağlam ve uygulanabilir bir çözüm ortaya koymaktadır. Bu çalışmada, CVSR'nin kararlı durum modeli türetilmiş ve güç akışı formülasyonlarına entegre edilmiştir. Önerilen model, iki paralel transformatörlü bir sistem kullanılarak doğrulanmış ve yoğun örgülü IEEE 342-Düğümlü Alçak Gerilim Şebeke Test Sistemi (LVNTS) üzerinde test edilmiştir. Simülasyon sonuçları, CVSR’nin güç akışını yeniden dağıtarak transformatör aşırı yüklenmesini etkili bir şekilde hafiflettiğini, böylece sistem esnekliğini artırdığını ve elektrik idarelerinin kapsamlı şebeke yenilemelerinden kaçınmasına veya bunları ertelemesine olanak tanıdığını göstermektedir.

Keywords

• tıkanıklık yönetimi
• güç akış kontrolü
• dağıtım sistemleri
• yük kaydırma
• örgü şebekeler

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