Name: balanced delta-delta power circuit
Uploaded: 2024-07-08T13:19:57.000Z
Duration: 1 min 17 s
Channel: JoVE

Dengeli bir delta-delta sistemi, delta bağlantılı bir kaynağa ve yüke sahiptir.
Delta bağlantılı kaynakların, hat voltajlarıyla aynı olan faz voltajlarını ifade etmek için pozitif sırada olduğu varsayılır.
Sıfır hat empedansları varsayarsak, faz gerilimleri empedanslar arasındaki voltajla eşleşir.
Faz akımları, faz başına faz gerilimi ve yük empedansının oranına eşittir.
Hat akımları, delta bağlı yüklerin düğümlerinde Kirchhoff'un Akım Yasası kullanılarak faz akımlarından türetilir.
Her hat akımı, karşılık gelen faz akımını 30 derece geciktirir ve büyüklüğü, faz akımının üç katının kareköküdür.
Alternatif olarak, delta-üçgen devresi, kaynak ve yük Y eşdeğerlerine dönüştürülerek analiz edilebilir.
Y bağlantılı kaynak için, karşılık gelen faz voltajı, delta bağlı kaynağın her bir hat voltajının üçün kareköküne bölünmesine eşittir ve fazı negatif 30 derece kaydırılır.
Y bağlantılı yük empedansı, üçgen bağlı yük empedansının üçe bölünmesine eşittir.
Şimdi, eşdeğer tek fazlı devre, üç hat akımını belirlemek için kullanılabilir.

Üçgen-Üçgen (Δ-Δ) devresi

Üçgen-üçgen konfigürasyonunda, kaynak ve yük üçgen şeklinde bağlanarak ağı üç farklı aşamaya bölen kapalı bir döngü oluşturur. Bu konfigürasyon, faz gerilimlerini hat gerilimleriyle aynı hale getirir. Kaynakların pozitif sırada olduğu varsayıldığında, faz gerilimleri nötr tel olmadan doğrudan ifade edilebilir.

<img alt="Equation 1" src="/files/ftp_upload/15131/15131_Equation_1.svg" style="height: 13px;">

Üçgen bağlantılı bir yükteki faz akımları, faz voltajının faz başına yük empedansına bölünmesiyle hesaplanır:

<img alt="Equation 2" src="/files/ftp_upload/15131/15131_Equation_2.svg" style="height: 32px;">

Bu konfigürasyonda, Kirchhoff'un Akım Yasası (KCL), her hat akımını kalan iki fazın akımlarının vektör toplamı olarak verir; bu, her hat akımının, faz akımının büyüklüğünün üç katının karekökü olduğu genel prensibine yol açar. Üçgen bağlantısının yarattığı faz farklılıklarından dolayı faz akımını 30 derece geride bırakır.

Bu tür sistemlerin analizleri, kaynak ve yükün yıldız eşdeğerlerine dönüştürülmesini içerir. Bu dönüşüm, üç fazlı sistemi tek fazlı eşdeğer devreye basitleştirir. Dönüşüm, üçgen bağlantılı kaynağın hat voltajlarının hem büyüklüğünü hem de fazını ayarlamayı içerir:

<img alt="Equation 3" src="/files/ftp_upload/15131/15131_Equation_3.svg" style="height: 32px;">

<img alt="Equation 4" src="/files/ftp_upload/15131/15131_Equation_4.svg" style="height: 16px;">

Ayrıca, yıldız bağlantılı her yükün empedansı, üçgen bağlantılı yükün empedansının üçte biri kadardır.

Dengeli üçgen-üçgen konfigürasyonları, yüksek güçlü makineler, transformatörler ve motor kontrol merkezleri için endüstriyel uygulamalarda kullanılır. Uzun mesafelerde etkili güç aktarımı sağlarlar, harmonik bozulmayı azaltırlar ve nötr bağlantıya ihtiyaç duymadan tutarlı voltaj seviyelerini koruyarak üç fazlı motorların düzgün çalışmasını kolaylaştırırlar.

Üçgen-Üçgen (Δ-Δ) Devresi

Dengeli bir delta-delta sistemi, delta bağlantılı bir kaynağa ve yüke sahiptir.
Delta bağlantılı kaynakların, ifade etmek için pozitif sırada olduğu varsayılır ...

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balanced delta-delta power circuit

A balanced delta-delta power circuit uses a delta-connected source and a delta-connected load. The two deltas form a closed loop that creates three separate phases. In this setup, the phase voltages are the same as the line voltages. If the source is in positive sequence, the phase voltages can be written directly, and no neutral wire is needed.

The delta-connected load current is found by dividing the phase voltage by the impedance of each phase. For line current, Kirchhoff’s Current Law (KCL) applies at each node. The line current is the vector sum of the currents from the other two phases. In a balanced delta connection, each line current has a magnitude of square root of three times the phase current. It also lags the phase current by 30 degrees because of the phase shift in the delta network.

To analyze the system more simply, the source and load can be changed into wye-equivalents. A wye connection is a star-shaped circuit that makes three-phase analysis easier. This conversion turns the three-phase network into a single-phase equivalent circuit. The delta-connected source voltages must be adjusted in both magnitude and phase during the conversion. The impedance of each wye-connected load is one-third of the delta-connected load impedance.

Balanced delta-delta systems are common in industrial settings. They are used for high-power machines, transformers, and motor control centers. They also support long-distance power transmission and can help reduce harmonic distortion. In three-phase motors, the steady voltage levels help smooth operation without the need for a neutral connection.

Balanced Delta-Delta Power Circuit

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the delta-to-delta circuit

A balanced delta-delta power circuit uses a delta-connected source and a delta-connected load. The two deltas form a closed loop that creates three separate phases. In this setup, the phase voltages are the same as the line voltages. If the source is in positive sequence, the phase voltages can be written directly, and no neutral wire is needed. The delta-connected load current is found by dividing the phase voltage by the impedance of each phase. For line current, Kirchhoff’s Current Law...

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Explore how balanced delta-delta power circuits work, including line and phase voltages, line current, wye-equivalent conversion, and industrial uses.

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JoVE Core Elektrik Mühendisliği, devre analizi teknikleriyle birlikte elektrik devrelerinin temel kavramlarını kapsayan, anlaşılması kolay animasyonlu videolar sunar. Operasyonel amplifikatörler ve devre dönüşümü kavramlarını kullanarak birinci dereceden ve ikinci dereceden devreleri içerir. Pratik tasarım örneklerinin ve gerçek dünya uygulamalarının bilim insanlarınca hazırlanan videolar aracılığıyla dahil edilmesi, karmaşık kavramları erişilebilir hale getirerek önemli bir eğitim değeri katmaktadır.

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Balanced Delta-Delta Power Circuit

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