Name: norton current in ac circuit analysis
Uploaded: 2024-04-11T12:48:50.000Z
Duration: 1 min 16 s
Channel: JoVE

Norton&#39;s theorem states that any two-terminal linear network can be replaced by an equivalent circuit consisting of a constant current source in parallel with an impedance.
To determine the value of the parallel impedance, the source is replaced with its internal impedance. This resultant circuit&#39;s equivalent impedance is the Norton impedance, which is the same as the Th&#233;venin impedance.
To determine the Norton current, place the sources again in the circuit, and analyze the open-circuit voltage, which is the Th&#233;venin voltage.
The Th&#233;venin voltage is determined by the product of the source current and the Thevenin impedance.
The same voltage is dropped across the load impedance as it is placed in a parallel configuration.
Recall the relationship between Norton current, Th&#233;venin voltage, and Th&#233;venin impedance. By substituting the values, it allows for the determination of the Norton current.
Norton&#39;s theorem is beneficial for analyzing and designing systems containing complex AC circuits.
By determining the Norton equivalent circuit for each stage or section of the complex circuit, the analysis of the overall system can be simplified.

norton equivalent circuits

Norton's theorem is a fundamental concept in the field of electrical engineering that allows for the simplification of complex AC circuits. The theorem states that any two-terminal linear network can be replaced with an equivalent circuit that consists of an impedance, which is parallel with a constant current source. Figure 1 shows the AC circuit portioned into two parts: Circuit A and Circuit B, while Figure 2 depicts the circuit obtained by replacing Circuit A by its Norton equivalent circuit.
<img alt="Two circuits in parallel diagram, showing Circuit A and B, connected by nodes a and b." src="/files/ftp_upload/15114/15114_PT_Figure_1.svg" style="text-align: center; height: 160px;" data-altupdatedat="1762173717000" data-alt="Figure1" />
Figure 1: A circuit portioned into two parts 
<img alt="Electrical circuit diagram; parallel circuit, current source, impedance Zt, nodes a-b." src="/files/ftp_upload/15114/15114_PT_Figure_2.svg" style="text-align: center; height: 160px;" data-altupdatedat="1762173717000" data-alt="Figure2" />
Figure 2: Norton equivalent circuit
To calculate the value of the parallel impedance, one must replace the source with its internal impedance, resulting in a circuit with an equivalent impedance known as the Norton impedance. The Norton impedance is the same as the Th&#233;venin impedance and is used to determine the Norton current, which is the current flowing through the circuit.
Determining the Norton current requires placing the sources back into the circuit and analyzing the open-circuit voltage, also known as the Th&#233;venin voltage. The value of the Th&#233;venin voltage is determined by multiplying the source current by the Thevenin impedance and is used to drop the same voltage across the load impedance when it is placed in a parallel configuration.
By using the relationship between the Norton current, the Th&#233;venin voltage, and the Norton current values, one can determine the Norton current of the circuit. This relationship makes Norton's theorem beneficial for analyzing and designing systems containing complex AC circuits since it simplifies their analysis by breaking the circuit down into smaller, more manageable sections.

Norton Equivalent Circuits

Norton&#39;s theorem states that any two-terminal linear network can be replaced by an equivalent circuit consisting of a constant current source in ...

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JoVE Core

Electrical Engineering

Unit 1

AC Circuit Analysis

KEY TERMS AND CONCEPTS

norton current in ac circuit analysis

Norton’s theorem helps simplify complex AC circuits by replacing a two-terminal linear network with a smaller equivalent circuit. That equivalent circuit uses an impedance in parallel with a constant current source. The method lets students break one complicated circuit into two parts and analyze them more easily.

To build the Norton equivalent, the source is replaced by its internal impedance. The result is the Norton impedance, which is the same as the Thévenin impedance. This parallel impedance is the key value used in the equivalent circuit.

Finding the Norton current takes one more step. The sources are placed back into the circuit, and the open-circuit voltage is analyzed. That voltage is also called the Thévenin voltage, and it can be found by multiplying the source current by the Thévenin impedance.

The Thévenin voltage helps show the same voltage drop across the load impedance when the load is arranged in parallel. Using the relationship between the Norton current, the Thévenin voltage, and the Norton impedance makes it possible to determine the circuit current. This makes Norton’s theorem useful for analyzing and designing systems with complex AC circuits because it turns a hard problem into smaller, more manageable parts.

Norton Current in AC Circuit Analysis

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Learn how Norton’s theorem simplifies complex AC circuits with a parallel current source and impedance, and how Norton current is determined from Thévenin values.

Norton Current in AC Circuit Analysis | 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

Norton Current in AC Circuit Analysis

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