Name: circuit source equivalents
Uploaded: 2025-05-22T09:06:14.000Z
Duration: 1 min 15 s
Channel: JoVE

Die Quellentransformationstechnik ermöglicht die Umwandlung einer Spannungsquelle in Reihe mit einem Widerstand in eine äquivalente Stromquelle parallel zum Widerstand oder umgekehrt.
Bei der Transformation bleiben die Widerstandswerte in der Schaltung gleich. Mit Hilfe des Ohmschen Gesetzes können die Werte der Spannung oder des Stroms bestimmt werden.
Der Pfeil der Stromquelle zeigt immer auf den Pluspol der Spannungsquelle.
Diese Technik kann aufgrund ihrer Innenwiderstandseigenschaften nicht auf ideale Spannungs- und Stromquellen angewendet werden.
Stellen Sie sich eine Schaltung vor, die aus einer Spannungsquelle, einer Stromquelle und einigen Widerständen besteht. Mit Hilfe der Source-Transformation kann der Spannungsabfall über dem Zentralwiderstand bestimmt werden.
Wenden Sie zunächst die Quellentransformation in beiden Quellen an, um die reduzierte Schaltung zu erhalten.
Wandeln Sie nun die linke Spannungsquelle wieder in eine Stromquelle um. Die Schaltung wird weiter vereinfacht und bietet eine Konfiguration mit einer einzigen Stromquelle.
Mit der Stromteilungsformel wird der Strom durch den Widerstand erhalten. Durch Substitution im Ohmschen Gesetz wird der Spannungsabfall am Widerstand erhalten.

quellentransformation

Quellenumwandlung ist eine grundlegende Technik, die in der Schaltungsanalyse angewendet wird und ein wertvolles Werkzeug zur Vereinfachung komplexer elektrischer Schaltkreise bietet. Diese Technik beinhaltet den Ersatz entweder einer Spannungsquelle in Serie mit einem Widerstand durch eine Stromquelle parallel zu einem Widerstand oder umgekehrt. Der Schlüsselbegriff hierbei ist, dass, wenn die ursprünglichen Quellen deaktiviert (ausgeschaltet) sind, der äquivalente Widerstand an den Endklemmen des Schaltkreises gleichbleibt. Es ist wichtig zu beachten, dass bei der Durchführung von Quellenumwandlungen der Pfeil der Stromquelle immer in Richtung des positiven Anschlusses der Spannungsquelle zeigt. Diese Konvention sorgt für Konsistenz und hilft dabei, die richtige Orientierung des Schaltkreises beizubehalten. Es ist jedoch erwähnenswert, dass die Quellenumwandlung nicht auf ideale Spannungsquellen anwendbar ist, da sie einen internen Widerstand von null besitzen. Im Gegensatz dazu haben nicht-ideale Spannungsquellen einen nicht-null internen Widerstand, was sie für die Quellenumwandlung geeignet macht. Ähnlich können ideale Stromquellen mit unendlichem internem Widerstand nicht durch endliche Spannungsquellen ersetzt werden. Um die praktische Anwendung der Quellenumwandlung zu veranschaulichen, betrachte man einen Schaltkreis, der individuell an eine nicht-ideale Spannungsquelle (Figure 1) und an eine nicht-ideale Stromquelle (Figure 2) angeschlossen ist. Wenn der Serienwiderstand dem Parallelwiderstand entspricht und die Spannung über die Spannungsquelle dem Ohmschen Gesetz folgt, werden diese nicht-idealen Quellen einander äquivalent. <img alt="Figure1" src="/files/ftp_upload/15051/15051_PT_Figure_1.svg" style="text-align: center; height: 128px;"> Figure 1: Schaltung mit nicht idealer Spannungsquelle. <img alt="Figure2" src="/files/ftp_upload/15051/15051_PT_Figure_2.svg" style="text-align: center; height: 128px;"> Figure 2: Schaltung mit nicht idealer Stromquelle Das Ersetzen der nichtidealen Spannungsquelle durch die äquivalente nichtideale Stromquelle ändert nichts an den Spannungs- oder Stromeigenschaften eines Elements innerhalb des Stromkreises. Dies zeigt die Leistungsfähigkeit der Quellentransformation bei der Vereinfachung der Schaltungsanalyse, ohne das Gesamtverhalten der Schaltung zu beeinträchtigen.

Quellentransformation

Die Quellentransformationstechnik ermöglicht die parallele Umwandlung einer Spannungsquelle in Reihe mit einem Widerstand in eine äquivalente Stromquelle ...

Education

Lehre

JoVE Core

Electrical Engineering

Elektrotechnik

Unit 1

Einheit 1

DC Circuit Analysis

DC-Schaltungsanalyse

KEY TERMS AND CONCEPTS

SCHLÜSSELBEGRIFFE UND KONZEPTE

Source Transformation

circuit source equivalents

Circuit source equivalents make it easier to simplify electrical circuits in circuit analysis. A source transformation replaces a voltage source in series with a resistor by a current source in parallel with a resistor, or it replaces a current source in parallel with a resistor by a voltage source in series with a resistor.

The key idea is that the equivalent resistance at the circuit terminals stays the same when the original sources are turned off. When making the change, the current source arrow must point toward the positive terminal of the voltage source. This keeps the circuit orientation consistent.

Source transformation does not work for ideal voltage sources because they have zero internal resistance. It also does not work for ideal current sources because they have infinite internal resistance. Nonideal voltage sources and nonideal current sources can be transformed because their internal resistance is not zero or infinite.

The transcript shows this idea with a nonideal voltage source and a nonideal current source. When the series resistance matches the parallel resistance, and the voltage across the voltage source follows Ohm's law, the two sources are equivalent. Replacing the nonideal voltage source with the matching nonideal current source does not change the voltage or current in any circuit element.

Circuit Source Equivalents

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source transformation

Circuit source equivalents make it easier to simplify electrical circuits in circuit analysis. A source transformation replaces a voltage source in series with a resistor by a current source in parallel with a resistor, or it replaces a current source in parallel with a resistor by a voltage source in series with a resistor. The key idea is that the equivalent resistance at the circuit terminals stays the same when the original sources are turned off. When making the change, the current source...

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key terms and concepts

Learn how source transformation replaces nonideal voltage and current sources while keeping terminal resistance the same in circuit analysis.

Circuit Source Equivalents | 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

Circuit Source Equivalents

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