Yenilenebilir enerji üretim sistemleri için kesintisiz geçişli şebeke bağlantılı 3-fazlı 4-kollu gelişmiş t-tipi evirici uygulaması
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Dosyalar
Tarih
2019
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Düzce Üniversitesi
Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
Alçak gerilim uygulamalarında verimliliği artırmak amacıyla 3-seviyeli T-tipi Nötr Noktası Bağlantılı (T-NPC) evirici yapısı sıkça kullanılmaktadır. Son zamanlarda, orta bacaktaki çift yönlü anahtarda düşük iletim kayıplarına sahip ters blokeli IGBT (Reverse Blocking IGBT, RB-IGBT) kullanılması ile daha verimli olan gelişmiş T-NPC (Advanced T-NPC, AT-NPC) evirici yapısı geliştirilmiştir. Şebeke hatası durumda evirici şebekeden ayrıldığında, geleneksel 3-fazlı 3-kollu eviricilerin faz gerilimleri dengesiz yükler tarafından etkilenir. Bu tez çalışmasının amacı alçak gerilim yenilenebilir enerji üretim sistemleri için ada modlu ve şebeke bağlantılı çalışabilen, bu çalışma modları arasında kesintisiz transfer sağlayabilen 3-fazlı 4-kollu AT-NPC yapısında 3-seviyeli eviricinin tasarımı, denetimi ve gerçekleştirilmesidir. Önerilen 3-fazlı 4-kollu evirici sistemiyle ada modunda 1-fazlı ve dengesiz 3-fazlı yük gruplarının dağıtık üretim üniteleri tarafından beslenmesi sağlanmaktadır. Önerilen evirici şebeke bağlantılı çalışmada Proportional Resonant (PR) tabanlı akım kontrollü olarak, ada modlu çalışmada ise Proportional Multi Resonant (PMR) tabanlı gerilim kontrollü olarak tasarlanmıştır. Bu çalışma modları arasında kesintisiz transfer sağlayabilmek için kaskat kesintisiz transfer yöntemi önerilmiştir. 3-seviyeli 4-kollu evirici için Taşıyıcı Tabanlı Darbe Genişlik Modülasyonu (TTDGM) tekniği ile 20 kHz anahtarlama sinyalleri üretilmiştir. 3-fazlı 4-kollu AT-NPC tipi 3-seviyeli evirici sisteminin deneysel testleri için 2,5 kVA gücünde bir laboratuvar prototipi kurulmuştur. Önerilen sistemin PSIM yazılımı aracılığıyla benzetimi ve PSIM/SimCoder yazılımı ile de model tabanlı gömülü kodlarının üretimi yapılmıştır. Eviricinin gerçek zamanlı denetimi ise TMS320F28335 sayısal işaret denetleyici kart (Digital Signal Controller, DSK) ile gerçekleştirilmiştir. Sonuç olarak önerilen kontrol yöntemi sayesinde evirici sistemi hem ada modlu hem de şebeke bağlantılı olarak çalıştırılmış ve bu çalışma modları arasında kesintisiz transfer gerçekleştirilmiştir.
In order to increase efficiency of the inverter, 3-level T-type Neutral Point Clamped (T-NPC) inverter structure is frequently used in low voltage applications. Recently, Advanced T-NPC (AT-NPC) inverter structure has been developed by using Reverse Blocking IGBT (RB-IGBT) with low conduction losses in the middle leg bidirectional switch. When the inverter disconnects from the grid in the event of a grid failure, the phase voltages of conventional 3-phase 3-leg inverters are affected by unbalanced loads. The object of this thesis is to design, control and implement a 3-level high efficiency inverter in 3-phase 4-leg AT-NPC topology capable of being operated in islanding and grid connected modes and of seamless transferring between these modes, for low voltage renewable disturbed generation systems. With the proposed 3-phase 4-leg inverter system, 1-phase and unbalanced 3-phase load groups in islanding mode can be fed by distributed generation units. The inverter is designed as current controlled based on Proportional Resonant (PR) controller in grid connected mode operation and designed as voltage controlled based on Proportional Multi Resonant (PMR) controller in islanding mode operation. In order to provide seamless transfer between these operating modes, cascade seamless transfer method is proposed by combined these control techniques in this work. For the 3-level inverter, 20 kHz switching signals are generated with Carrier Based PWM (CBPWM) technique. A laboratory prototype 2,5 kVA rated power of 3-pahse 4-leg AT-NPC type 3-level inverter system has been installed. Simulation studies of the proposed system have been carried out via PSIM software and model-based embedded codes generation for Digital Signal Controller (DSC) have been carried out with PSIM/SimCoder software. The real time controlling of the inverter system is achieved with TMS320F28335 DSC card. As a result, with the proposed control method, the inverter is operated in both island mode and grid connected mode and seamless transfer between these operating modes has been realized.
In order to increase efficiency of the inverter, 3-level T-type Neutral Point Clamped (T-NPC) inverter structure is frequently used in low voltage applications. Recently, Advanced T-NPC (AT-NPC) inverter structure has been developed by using Reverse Blocking IGBT (RB-IGBT) with low conduction losses in the middle leg bidirectional switch. When the inverter disconnects from the grid in the event of a grid failure, the phase voltages of conventional 3-phase 3-leg inverters are affected by unbalanced loads. The object of this thesis is to design, control and implement a 3-level high efficiency inverter in 3-phase 4-leg AT-NPC topology capable of being operated in islanding and grid connected modes and of seamless transferring between these modes, for low voltage renewable disturbed generation systems. With the proposed 3-phase 4-leg inverter system, 1-phase and unbalanced 3-phase load groups in islanding mode can be fed by distributed generation units. The inverter is designed as current controlled based on Proportional Resonant (PR) controller in grid connected mode operation and designed as voltage controlled based on Proportional Multi Resonant (PMR) controller in islanding mode operation. In order to provide seamless transfer between these operating modes, cascade seamless transfer method is proposed by combined these control techniques in this work. For the 3-level inverter, 20 kHz switching signals are generated with Carrier Based PWM (CBPWM) technique. A laboratory prototype 2,5 kVA rated power of 3-pahse 4-leg AT-NPC type 3-level inverter system has been installed. Simulation studies of the proposed system have been carried out via PSIM software and model-based embedded codes generation for Digital Signal Controller (DSC) have been carried out with PSIM/SimCoder software. The real time controlling of the inverter system is achieved with TMS320F28335 DSC card. As a result, with the proposed control method, the inverter is operated in both island mode and grid connected mode and seamless transfer between these operating modes has been realized.
Açıklama
YÖK Tez No: 618476
Anahtar Kelimeler
Elektrik ve Elektronik Mühendisliği, Electrical and Electronics Engineering, Dengesiz yük kontrolü, Off-balance control, Gerilim kontrolü, Voltage control, Güç çeviriciler, Power converters
