Name: delta-wye source and load connections
Uploaded: 2024-07-08T13:19:57.000Z
Duration: 1 min 16 s
Channel: JoVE

Un sistema bilanciato da triangolo a Y è dotato di una sorgente bilanciata collegata a triangolo che alimenta un carico bilanciato collegato a Y.
In questo circuito delta-Y, si presume che una sequenza abc positiva esprima le tensioni di fase, che fungono anche da tensioni di linea della sorgente collegata a delta.
La legge della tensione di Kirchhoff può essere applicata a un anello nel circuito per derivare una relazione tra due delle correnti di linea.
Poiché si assume una sequenza positiva, queste correnti di linea hanno una differenza di fase di 120 gradi, che viene utilizzata per determinarne una.
Le altre due correnti di linea sono ottenute utilizzando la sequenza di fase positiva.
Le correnti di fase del circuito delta-Y sono approssimativamente uguali alle correnti di linea.
In alternativa, la sorgente collegata a delta può essere sostituita con la sorgente equivalente collegata a Y.
Il circuito Y-Y ottenuto viene analizzato considerando un circuito monofase equivalente e determinando le correnti a tre linee.
Questo circuito può anche essere trasformato in un sistema delta-delta a scopo di analisi, poiché il carico collegato al delta è spesso preferito a causa della facilità di modifica dei singoli carichi.

il circuito triangolo-stella

Nel circuito triangolo-stella, la sorgente è collegata a triangolo, mentre il carico è in configurazione a stella. Ciò significa che la tensione di fase della sorgente collegata a triangolo è uguale alla tensione di linea del carico collegato a stella. La connessione tra le correnti a due linee ha origine dalla sorgente collegata a triangolo. La differenza di fase nel sistema bilanciato consente di calcolare la corrente di una linea rispetto all'altra, utilizzando la sequenza positiva delle fasi. Nel sistema triangolo-stella, le correnti di fase nel carico collegato a stella sono direttamente uguali alle correnti di linea dalla sorgente a triangolo, a causa della configurazione a stella del carico che semplifica il flusso della sorgente delta. La relazione tra le correnti di linea e di fase in una configurazione a stella mostra che la corrente di fase nel carico collegato a stella è uguale alla corrente di linea della sorgente collegata a triangolo.


Un altro modo per ottenere le correnti di linea è sostituire la sorgente collegata a triangolo con la sua sorgente equivalente collegata a stella. Le tensioni linea-linea di una sorgente collegata a stella anticipano le tensioni di fase corrispondenti di 30 gradi. Ciò significa che ciascuna tensione di fase della sorgente equivalente collegata a stella si ottiene dividendo la corrispondente tensione di linea della sorgente collegata a triangolo per la radice quadrata di tre e spostandone la fase di -30 gradi. Di conseguenza, la sorgente equivalente collegata a stella ha tensioni di fase spostate di 120 gradi.


Convertendo una configurazione a triangolo in una configurazione a stella, il sistema può ottenere una migliore regolazione della tensione e consentire l'uso di un filo neutro. Questo filo neutro consente la messa a terra del sistema, migliorando la sicurezza e la stabilità.


La configurazione bilanciata triangolo-triangolo viene utilizzata per trasmettere elettricità su lunghe distanze, dove i livelli di alta tensione devono essere ridotti a livelli utilizzabili per uso industriale, commerciale e residenziale.

Il Circuito Triangolo-Stella

Un sistema bilanciato da triangolo a Y è dotato di una sorgente bilanciata collegata a triangolo che alimenta un carico bilanciato collegato a Y.
In questo circuito delta-Y, un abc positivo ...

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The Delta-to-Y Circuit

delta-wye source and load connections

A balanced delta-wye circuit connects a delta-connected source to a wye-connected load. In this setup, the phase voltage of the delta source equals the line voltage of the wye load. The source also sets the line currents that flow into the load.

For a balanced system, the phase difference between currents makes it possible to find one line current from the other by using the positive sequence of phases. In the wye-connected load, each phase current equals the line current from the delta source. That relationship makes current analysis simpler in the load section.

The line currents can also be found by replacing the delta source with an equivalent wye source. In that conversion, each phase voltage is the matching line voltage divided by the square root of three and shifted by -30 degrees. The line-to-line voltages of a wye source lead the phase voltages by 30 degrees, so the equivalent wye source keeps the phases spaced 120 degrees apart.

Changing a delta connection to a star, or wye, connection can improve voltage regulation. It also allows the use of a neutral wire. That neutral wire supports grounding, which improves safety and stability. Balanced delta systems are also used for long-distance power transmission, where high voltage must later be stepped down for industrial, commercial, and residential use.

Delta-Wye Source and Load Connections

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A balanced delta-wye circuit connects a delta-connected source to a wye-connected load. In this setup, the phase voltage of the delta source equals the line voltage of the wye load. The source also sets the line currents that flow into the load. For a balanced system, the phase difference between currents makes it possible to find one line current from the other by using the positive sequence of phases. In the wye-connected load, each phase current equals the line current from the delta source.

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Learn how a balanced delta source powers a wye load, how line and phase currents relate, and how a delta source can be converted to an equivalent wye source.

Delta-Wye Source and Load Connections | JoVE K12

JoVE Core Electrical Engineering offers easy-to-understand animated videos that cover fundamental concepts of electric circuits along with circuit analysis techniques. It incorporates first-order and second-order circuits using operational amplifiers and circuit transformation concepts. The inclusion of practical design examples and real-world applications through scientist-in-action videos adds significant educational value, making complex concepts accessible.

electrical engineering

Delta-Wye Source and Load Connections

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