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

Ein symmetrisches Delta-zu-Y-System verfügt über eine symmetrische Delta-verbundene Quelle, die eine symmetrische Y-verbundene Last mit Strom versorgt.
In dieser Delta-Y-Schaltung wird eine positive abc-Sequenz angenommen, um die Phasenspannungen auszudrücken, die auch als Netzspannungen der delta-verbundenen Quelle dienen.
Das Kirchhoffsche Spannungsgesetz kann auf eine Schleife in der Schaltung angewendet werden, um eine Beziehung zwischen zwei der Netzströme abzuleiten.
Da eine positive Abfolge angenommen wird, haben diese Leitungsströme eine Phasendifferenz von 120 Grad, anhand derer einer von ihnen bestimmt wird.
Die beiden anderen Netzströme werden mit Hilfe der positiven Phasenfolge erhalten.
Die Phasenströme der Delta-Y-Schaltung entsprechen in etwa den Netzströmen.
Alternativ kann die delta-verbundene Quelle durch die entsprechende Y-verbundene Quelle ersetzt werden.
Die erhaltene Y-Y-Schaltung wird analysiert, indem eine äquivalente einphasige Schaltung betrachtet und die dreipoligen Ströme bestimmt werden.
Diese Schaltung kann zu Analysezwecken auch in ein Delta-Delta-System umgewandelt werden, da die Delta-verbundene Last aufgrund der einfachen Änderung einzelner Lasten oft bevorzugt wird.

der delta-zu-stern-schaltkreis

Im Delta-Stern-Schaltkreis ist die Quelle im Delta angeschlossen, während die Last in einer Sternkonfiguration vorliegt. Dies bedeutet, dass die Phasenspannung der im Delta angeschlossenen Quelle gleich der Leitungsspannung der im Stern angeschlossenen Last ist. Die Verbindung zwischen zwei Leitungsströmen stammt von der im Delta angeschlossenen Quelle. Die Phasendifferenz im ausgeglichenen System ermöglicht die Berechnung eines Leitungsstroms aus dem anderen unter Verwendung der positiven Phasenfolge. Im Delta-Stern-System sind die Phasenströme in der im Stern angeschlossenen Last direkt gleich den Leitungsströmen aus der Delta-Quelle, da die Sternkonfiguration der Last den Fluss aus der Delta-Quelle vereinfacht. Die Beziehung zwischen den Leitungs- und Phasenströmen in einer Sternkonfiguration zeigt, dass der Phasenstrom in der im Stern angeschlossenen Last gleich dem Leitungsstrom der im Delta angeschlossenen Quelle ist.

Eine andere Möglichkeit, die Leitungsströme zu erhalten, besteht darin, die Quelle mit Dreieckschaltung durch ihre äquivalente Quelle mit Sternschaltung zu ersetzen. Die Leitungsspannungen einer Quelle mit Sternschaltung eilen ihren entsprechenden Phasenspannungen um 30 Grad voraus. Dies bedeutet, dass jede Phasenspannung der äquivalenten Quelle mit Sternschaltung erhalten wird, indem die entsprechende Leitungsspannung der Quelle mit Dreieckschaltung durch die Quadratwurzel aus drei geteilt und ihre Phase um -30 Grad verschoben wird. Infolgedessen weist die äquivalente Quelle mit Sternschaltung entsprechend um 120 Grad verschobene Phasenspannungen auf.

Durch die Umwandlung einer Dreieckkonfiguration in eine Sternkonfiguration kann das System eine bessere Spannungsregelung erreichen und die Verwendung eines Neutralleiters ermöglichen. Dieser Neutralleiter ermöglicht die Erdung des Systems und erhöht so die Sicherheit und Stabilität.

Die symmetrische Dreieck-Dreieck-Konfiguration wird zur Übertragung von Elektrizität über lange Entfernungen verwendet, wobei hohe Spannungspegel auf nutzbare Pegel für die industrielle, gewerbliche und private Nutzung heruntertransformiert werden müssen.

Der Delta-zu-Stern-Schaltkreis

Ein symmetrisches Delta-zu-Y-System verfügt über eine symmetrische Delta-verbundene Quelle, die eine symmetrische Y-verbundene Last mit Strom versorgt.
In dieser Delta-Y-Schaltung wird ein positives Abc ...

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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

three-phase circuits

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the delta-to-y circuit

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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key terms and concepts

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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