Name: circuit source symbols and controls
Uploaded: 2024-04-11T12:48:28.000Z
Duration: 1 min 18 s
Channel: JoVE

As fontes em um circuito podem ser independentes ou dependentes.
Fontes independentes de tensão ou corrente fornecem tensão e corrente não afetadas por outros elementos do circuito.
Os símbolos de fontes de tensão independentes têm polaridades, enquanto as fontes de corrente independentes usam setas para indicar a direção da corrente.
Um curto-circuito é uma fonte de tensão independente de tensão zero, enquanto um circuito aberto é uma fonte de corrente independente de corrente zero.
Fontes dependentes são geradores de tensão ou corrente controlados por outros elementos do circuito. Eles são representados por uma forma de diamante.
Com base em suas partes controladoras e controladas, as fontes dependentes são divididas em quatro categorias.
Considere um circuito em que a tensão da fonte dependente é controlada pela corrente através do resistor.
Se um curto-circuito for adicionado em série com o resistor, a corrente de controle é equivalente à corrente no curto-circuito.
A relação entre a tensão da fonte e a corrente de controle representa o ganho da fonte dependente.
Da mesma forma, a tensão de controle pode ser considerada como tensão de circuito aberto.
Portanto, a tensão ou corrente das fontes dependentes é proporcional à tensão ou corrente de controle.

fontes independentes e dependentes

Nos circuitos elétricos, as fontes desempenham um papel crucial no fornecimento de energia para a operação do circuito. Essas fontes podem ser amplamente categorizadas em dois tipos: independentes e dependentes.

Fontes independentes de tensão ou corrente fornecem uma quantidade fixa de tensão ou corrente, respectivamente, que não é afetada por outros elementos do circuito. Elas são representadas por meio de símbolos específicos. Fontes de tensão independentes são simbolizadas com polaridades (+ e -), indicando a direção da diferença de potencial, enquanto fontes de corrente independentes usam setas para indicar a direção do fluxo de corrente.

Um aspecto interessante das fontes independentes é que um curto-circuito pode ser considerado uma fonte de tensão independente de zero volts porque permite que a corrente flua livremente sem queda de tensão. Por outro lado, um circuito aberto pode ser pensado como uma fonte de corrente independente de zero amperes, visto que impede qualquer fluxo de corrente independentemente da tensão aplicada.

Por outro lado, fontes dependentes são geradores de tensão ou corrente cujos valores são controlados por outros elementos dentro do mesmo circuito. Elas são representadas por um símbolo de diamante nos diagramas de circuitos.

Essas fontes dependentes são ainda divididas em quatro categorias com base em suas partes controladas e controladoras: fontes de tensão controladas por tensão (FTCT), fontes de tensão controladas por corrente (FTCC), fontes de corrente controladas por tensão (FCCT) e fontes de corrente controladas por corrente. (FCCC).

Por exemplo, num circuito onde a saída de tensão de uma fonte dependente é controlada pela corrente que flui através de um resistor, se um curto-circuito for adicionado em série com esse resistor, a corrente de controle torna-se equivalente à corrente no curto-circuito. A relação entre a tensão da fonte e a corrente de controle representa o ganho da fonte dependente.

Da mesma forma, a tensão de controle pode ser considerada tensão de circuito aberto. Isso significa que a tensão ou corrente das fontes dependentes é proporcional à tensão ou corrente de controle.

Fontes independentes e dependentes

As fontes em um circuito podem ser independentes ou dependentes.
Fontes independentes de tensão ou corrente fornecem tensão e corrente não afetadas por outros circuitos ...

Education

JoVE Core

Electrical Engineering

Engenharia Elétrica

Unit 1

Unidade 1

Basics of Electric Circuits

Fundamentos de Circuitos Elétricos

KEY TERMS AND CONCEPTS

TERMOS E CONCEITOS-CHAVE

Independent and Dependent Sources

circuit source symbols and controls

Circuit sources in electrical circuits can be independent or dependent. They provide the power a circuit needs to operate. Independent voltage sources supply a fixed voltage, and independent current sources supply a fixed current. Their output does not change because of other parts in the circuit.

These sources use standard symbols in circuit diagrams. An independent voltage source is shown with + and - signs to mark the potential difference. An independent current source is shown with an arrow to show the direction of current flow. A short circuit can be treated as a zero-voltage independent voltage source because it allows current to flow with no voltage drop. An open circuit can be treated as a zero-current independent current source because it blocks current flow even when voltage is applied.

Dependent sources work differently. Their voltage or current is controlled by another element in the same circuit. They are drawn with a diamond shape. There are four types: voltage-controlled voltage sources, current-controlled voltage sources, voltage-controlled current sources, and current-controlled current sources.

The controlling part can be tied to a resistor or another circuit element. For example, if the output voltage of a dependent source is controlled by the current through a resistor, adding a short circuit in series with that resistor makes the controlling current the same as the current in the short circuit. The ratio of the source voltage to the controlling current gives the gain of the dependent source. In a similar way, the controlling voltage can be treated as an open-circuit voltage. This means the voltage or current from a dependent source is proportional to the controlling voltage or current.

Circuit Source Symbols and Controls

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electric circuit elements

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circuit terminology

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independent and dependent sources

Circuit sources in electrical circuits can be independent or dependent. They provide the power a circuit needs to operate. Independent voltage sources supply a fixed voltage, and independent current sources supply a fixed current. Their output does not change because of other parts in the circuit. These sources use standard symbols in circuit diagrams. An independent voltage source is shown with + and - signs to mark the potential difference. An independent current source is shown with an...

ohm's law

Resistance and Conductance in Circuits

Resistance and conductance help explain how electric current moves through a circuit. Resistors are basic circuit parts made from metallic alloys or carbon compounds. They are used to model how a material resists current and to control and regulate electrical power in a circuit. Ohm's law describes the link between voltage and current across a resistor. The voltage across a resistor is directly proportional to the current through it. The constant that sets this relationship is resistance.

kirchhoff's current law

Kirchhoff's Current Law at Circuit Nodes

Kirchhoff's Current Law explains how current behaves at a circuit node. A node is the point where two or more circuit elements meet. The law says the current entering a node equals the current leaving it. That balance follows the rule of charge conservation, which means electric charge is not lost at the junction. When applying KCL, currents entering the node are treated as positive and currents leaving the node are treated as negative. The currents can be added algebraically at the node, and...

kirchhoff's voltage law

Voltage Balance in Closed Circuit Loops

Kirchhoff's Voltage Law explains how voltage is balanced in a closed circuit loop. It is a basic rule in electrical engineering and comes from the idea of energy conservation. Energy can change form, but it cannot be created or destroyed. KVL states that the algebraic sum of all voltages around a closed path, or loop, is zero. In other words, the total voltage supplied in a loop equals the total voltage drop across the components in that loop. A loop can be traced clockwise or anticlockwise,...

voltage dividers

Series Resistors and Voltage Split

Series resistors split voltage across a circuit. In a series setup, resistors are linked one after another. The same current flows through each resistor in the chain. To analyze this behavior, Ohm's law is used to relate voltage, current, and resistance. Kirchhoff's voltage law says the voltages around a series loop add up to the source voltage. That means the current in the circuit equals the source voltage divided by the total resistance in series. The current value can then be used in Ohm's...

current dividers

Parallel Resistors and Current Division

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key terms and concepts

Learn how independent and dependent sources work in circuits, how they are drawn, and how control by voltage or current determines dependent source gain.

Circuit Source Symbols and Controls | 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 Symbols and Controls

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