Name: analyzing circuits with superposition
Uploaded: 2024-04-11T12:48:31.000Z
Duration: 1 min 18 s
Channel: JoVE

Der Superpositionssatz wird in Schaltkreisen mit mehreren unabhängigen Quellen verwendet.
Um dieses Theorem anzuwenden, behalten Sie jeweils eine unabhängige Quelle bei, während Sie die inaktive Spannungsquelle durch einen Kurzschluss bzw. die inaktive Stromquelle durch einen offenen Stromkreis ersetzen.
Der Satz besagt, dass die Spannung über oder der Strom durch ein Element in einer linearen Schaltung die algebraische Summe der Beiträge der unabhängigen Quellen ist.
Stellen Sie sich eine Schaltung mit einer Spannungs- und einer Stromquelle vor, bei der der Spannungsabfall an einem Widerstand bestimmt werden muss.
Der Spannungsabfall hat Beiträge aus beiden unabhängigen Quellen.
Der Beitrag der Spannungsquelle wird erhalten, indem die Stromquelle auf Null gesetzt wird.
Durch Anwendung des Kirchhoffschen Spannungsgesetzes wird der Schleifenstrom bestimmt. Mit dem Ohmschen Gesetz wird der Spannungsabfall berechnet.
In ähnlicher Weise wird der Beitrag der Stromquelle erhalten, indem die Spannungsquelle auf Null gesetzt wird.
Durch die Kombination der Widerstände wird der äquivalente Widerstand erhalten. Mit Hilfe der Stromteilungsregel und des Ohmschen Gesetzes wird der Spannungsabfall bestimmt.
Durch Addieren der Beiträge aus unabhängigen Quellen wird schließlich der Gesamtspannungsabfall über den Widerstand erhalten.

superpositionssatz

Das Superpositionsprinzip ist ein grundlegendes Konzept, das besagt, dass in einem linearen Schaltkreis die Spannung über (oder der Strom durch) ein Element bestimmt werden kann, indem die individuellen Beiträge jeder unabhängigen Quelle, die isoliert wirkt, summiert werden. Bei der Analyse von linearen Schaltungen mit mehreren unabhängigen Quellen dient dieses Prinzip als wertvolles Werkzeug. Um das Superpositionsprinzip effektiv anzuwenden, sollte man sich jeweils auf eine einzige unabhängige Quelle konzentrieren, während alle anderen deaktiviert werden. Dieser Ansatz liefert den Ausgang (Spannung oder Strom), der aus der aktiven Quelle resultiert. Die kumulative Wirkung aller aktiven Quellen kann dann durch algebraisches Addieren ihrer individuellen Beiträge bestimmt werden. Dies vereinfacht den Prozess der Schaltungsanalyse. Bemerkenswert ist, dass abhängige Quellen unberührt bleiben, da sie von Schaltungsvariablen gesteuert werden. Es ist erwähnenswert, dass die Nutzung des Superpositionsprinzips zu einem erhöhten analytischen Aufwand führen kann. Beispielsweise muss man bei der Analyse eines Schaltkreises mit drei unabhängigen Quellen drei separate, vereinfachte Schaltkreise analysieren, wobei jeder den Beitrag einer individuellen Quelle darstellt. Trotz dieses potenziellen Nachteils bleibt das Superpositionsprinzip eine wertvolle Technik zur Vereinfachung komplexer Schaltungen, indem Spannungsquellen durch Kurzschlüsse und Stromquellen durch offene Schaltungen ersetzt werden.

Superpositionssatz

Der Superpositionssatz wird in Schaltkreisen mit mehreren unabhängigen Quellen verwendet.
Um dieses Theorem anzuwenden, behalten Sie jeweils eine unabhängige Quelle, während ...

Education

Lehre

JoVE Core

Electrical Engineering

Elektrotechnik

Unit 1

Einheit 1

DC Circuit Analysis

DC-Schaltungsanalyse

KEY TERMS AND CONCEPTS

SCHLÜSSELBEGRIFFE UND KONZEPTE

Superposition Theorem

analyzing circuits with superposition

Superposition is a circuit analysis method for linear circuits with more than one independent source. It lets you find the voltage across or current through an element by adding the separate effects of each source acting alone.

To use superposition, keep one independent source active and turn off the others. A voltage source is replaced by a short circuit, and a current source is replaced by an open circuit. Then calculate the output from the single active source.

Repeat the process for each independent source in the circuit. The final voltage or current is found by algebraically adding the individual results. Dependent sources are not turned off because they depend on circuit variables.

This method can simplify complex circuits, but it may take more work. A circuit with three independent sources must be analyzed as three separate simplified circuits. Even so, superposition remains a useful tool for breaking down difficult linear circuit problems.

Analyzing Circuits with Superposition

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superposition theorem

Superposition is a circuit analysis method for linear circuits with more than one independent source. It lets you find the voltage across or current through an element by adding the separate effects of each source acting alone. To use superposition, keep one independent source active and turn off the others. A voltage source is replaced by a short circuit, and a current source is replaced by an open circuit. Then calculate the output from the single active source. Repeat the process for each...

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Thevenin Circuit Equivalents

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norton's theorem

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key terms and concepts

Learn how superposition helps solve linear circuits by analyzing one independent source at a time, then adding the voltage or current contributions.

Analyzing Circuits with Superposition | 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

Analyzing Circuits with Superposition

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