Name: norton equivalent circuit in dc analysis
Uploaded: 2024-04-11T12:48:31.000Z
Duration: 1 min 14 s
Channel: JoVE

O teorema de Norton afirma que qualquer circuito linear de dois terminais pode ser substituído por um circuito equivalente que consiste em uma única fonte de corrente em paralelo com um resistor.
Para implementar o teorema de Norton, remova o resistor de carga dos dois terminais de carga: a rede restante será substituída pelo circuito equivalente de Norton, conforme visto nesses terminais.
A resistência do Norton pode ser determinada definindo todas as fontes independentes como zero. O equivalente ou resistência de entrada entre os terminais é a resistência do Norton.
Para encontrar a corrente de Norton, retorne todas as fontes às suas posições originais. Em seguida, calcule a corrente do Norton encontrando a corrente de curto-circuito entre os terminais marcados.
Por fim, substitua a rede pelo circuito equivalente do Norton e conecte o resistor de carga novamente.
A técnica de transformação de origem pode ser usada para converter entre circuitos equivalentes de Norton e Thévenin.
A tensão de circuito aberto, a corrente de curto-circuito e a resistência de entrada ou equivalente devem ser conhecidas para determinar o circuito equivalente de Thevenin ou Norton.
A estreita relação entre os teoremas de Norton e Thévenin e a lei de Ohm ajuda a resolver circuitos elétricos complexos.

teorema de norton

O teorema de Norton é um princípio fundamental que afirma que um circuito linear de dois terminais pode ser substituído por um circuito equivalente, que compreende uma fonte de corrente (ⅠN) em paralelo com um resistor (RN). Aqui, ⅠN representa a corrente de curto-circuito que flui através dos terminais, e RN representa a entrada ou resistência equivalente nos terminais quando todas as fontes independentes estão desativadas. Isto implica que o circuito ilustrado na Figura (a) pode ser trocado pelo representado na Figura (b).

<img alt="Figure1" src="/files/ftp_upload/15054/15054_PT_Figure_1.svg" style="text-align: center; height: 132px;" />

Figure (a)

<img alt="Figure1" src="/files/ftp_upload/15054/15054_PT_Figure_2.svg" style="text-align: center; height: 132px;" />

Figure (b)

A determinação da resistência de Norton envolve o processo de configurar todas as fontes independentes dentro do circuito para zero. O valor resultante representa a resistência de Norton, essencial para a aplicação do teorema. Para calcular a corrente de Norton, deve-se restaurar todas as fontes para suas configurações originais e, em seguida, verificar a corrente de curto-circuito entre os terminais marcados. Substituir a rede pelo circuito equivalente de Norton e reconectar o resistor de carga é necessário para completar a transformação. Para estabelecer tanto o circuito equivalente de Thévenin quanto o de Norton, é necessário ter conhecimento da tensão de circuito aberto, da corrente de curto-circuito e da resistência de entrada ou equivalente. Esses parâmetros servem como entradas cruciais para essas transformações de circuito. A estreita relação entre os teoremas de Norton e Thévenin é dada pelas seguintes esquações:

<img alt="Equation1" src="/files/ftp_upload/15054/15054_PT_Equation_1.svg" style="text-align: center; height: 14px;" />

<img alt="Equation1" src="/files/ftp_upload/15054/15054_PT_Equation_2.svg" style="text-align: center; height: 34px;" />

combinada com os princípios da lei de Ohm, fornece ferramentas valiosas para resolver circuitos elétricos complexos.

Teorema de Norton

O teorema de Norton afirma que qualquer circuito linear de dois terminais pode ser substituído por um circuito equivalente que consiste em uma única fonte de corrente em ...

Education

JoVE Core

Electrical Engineering

Engenharia Elétrica

Unit 1

Unidade 1

DC Circuit Analysis

Análise de Circuitos CC

KEY TERMS AND CONCEPTS

TERMOS E CONCEITOS-CHAVE

Norton's Theorem

norton equivalent circuit in dc analysis

Norton equivalent circuit in DC analysis shows how a linear two-terminal circuit can be replaced by a simpler network. The replacement uses a current source, called I_N, in parallel with a resistor, called R_N. I_N is the short-circuit current through the terminals, and R_N is the input or equivalent resistance seen at the terminals when the independent sources are turned off.

To find Norton's resistance, all independent sources in the circuit are set to zero. The resistance measured at the marked terminals is then taken as R_N. To find Norton's current, the sources are restored to their original values and the short-circuit current between the terminals is found.

After the Norton equivalent is built, the load resistor is connected again to complete the transformation. This method gives a compact way to study how the circuit behaves at its terminals. It is closely linked to Thevenin's theorem, since both use the open-circuit voltage, short-circuit current, and equivalent resistance.

These relationships, together with Ohm's law, help solve more complex electrical circuits. By converting a network into its Norton form, students can compare terminal behavior more easily. The theorem is a useful tool for circuit analysis when a two-terminal linear network must be simplified.

Norton Equivalent Circuit in DC Analysis

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Norton equivalent circuit in DC analysis shows how a linear two-terminal circuit can be replaced by a simpler network. The replacement uses a current source, called I_N, in parallel with a resistor, called R_N. I_N is the short-circuit current through the terminals, and R_N is the input or equivalent resistance seen at the terminals when the independent sources are turned off. To find Norton's resistance, all independent sources in the circuit are set to zero. The resistance measured at the...

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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

Norton Equivalent Circuit in DC Analysis

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