Name: finding voltage and impedance in circuit a
Uploaded: 2025-05-22T09:06:14.000Z
Duration: 1 min 18 s
Channel: JoVE

배전선과 변압기를 포함하는 가정용 배전 시스템은 소스 네트워크로 간주될 수 있습니다.
집 내부에서는 다양한 전기 제품을 부하 임피던스로 나타낼 수 있습니다.
Thévenin의 정리는 이 복잡한 분배 시스템을 Thévenin 등가 회로로 단순화합니다.
Thévenin 등가 회로를 찾으려면 Thévenin 전압과 Thévenin 임피던스의 두 가지 매개변수에 대한 지식이 필요합니다.
이를 결정하는 과정을 이해하려면 전압 소스에 연결된 단순화된 RLC 회로를 고려하십시오.
Thévenin 임피던스를 계산하려면 전압 소스를 단락으로 교체하고 회로의 등가 임피던스를 결정하십시오.
Thévenin 전압은 개방 회로 전압과 동일하며 회로의 병렬 분기를 통과하는 전압 강하와 동일합니다.
처음에는 회로의 닫힌 메쉬를 통해 흐르는 전류가 계산됩니다. 그런 다음 옴의 법칙을 사용하여 병렬 분기 양단의 전압 강하가 결정되어 Thévenin 전압을 제공합니다.
회로에 서로 다른 주파수에서 작동하는 소스가 있는 경우 Thévenin 등가 회로와 커패시터 및 인덕터 임피던스는 각 주파수에 대해 별도로 결정해야 합니다.

테브낭 등가 회로

배전선과 변압기를 포함하는 가정용 배전 시스템이 1차 네트워크 역할을 합니다. 가정 내 전기 제품은 부하 온저항으로 표현될 수 있습니다. 이 복잡한 분배 시스템을 단순화하기 위해 테브낭의 정리를 적용하여 테브낭 등가 회로를 만들 수 있습니다. AC 회로가 두 부분(회로 A와 회로 B)으로 분할된 경우 Figure 1과 같이 단일 단자 쌍으로 연결됩니다.

<img alt="Figure1" src="/files/ftp_upload/15113/15113_PT_Figure_1.svg" style="text-align: center; height: 140px;">
Figure 1: 두 부분으로 나누어진 회로

<img alt="Figure2" src="/files/ftp_upload/15113/15113_PT_Figure_2.svg" style="text-align: center; height: 150px;">
 Figure 2: 테브낭 등가 회로로 대체된 회로 A

회로 A를 테브낭 등가 회로(온저항과 직렬로 연결된 전압 소스)로 교체해도 회로 B(Figure 2 참조)의 어떤 요소의 전류나 전압도 변경되지 않습니다. 회로 B의 모든 회로 요소의 전류 및 전압 값은 회로 B가 회로 A 또는 해당 테브낭 등가물에 연결되어 있는지 여부에 관계없이 동일합니다. 테브낭 등가 회로를 찾으려면 테브낭 전압과 테브낭 온저항이라는 두 가지 매개변수가 필요합니다. Figure 3은 개방 회로 전압 과정c 를 결정하기 위해 회로 A의 단자에 연결된 개방 회로를 보여주며, Figure 4는 테브낭 온저항 Z_t 가 회로 A*의 등가 온저항임을 나타냅니다.

<img alt="Figure3" src="/files/ftp_upload/15113/15113_PT_Figure_3.svg" style="text-align: center; height: 96px;">
Figure 3: 과정c 를 사용한 테브낭 등가 회로.

<img alt="Figure4" src="/files/ftp_upload/15113/15113_PT_Figure_4.svg" style="text-align: center; height: 96px;">
Figure 4: Z_t 를 보여주는 테브낭 등가 회로.

회로 A*는 모든 독립 전압 소스를 단락 회로로 교체하고 모든 독립 전류 소스를 개방 회로로 대체하여 회로 A로부터 구성됩니다. 일반적으로 테브낭 온저항 Z_t 는 직렬 또는 병렬 온저항을 등가 온저항으로 반복적으로 대체하여 결정할 수 있습니다.

배전선과 변압기를 포함하는 가정용 배전 시스템은 소스 네트워크로 간주될 수 있습니다.
집 안에서, ...

Education

교육

JoVE Core

Electrical Engineering

전기공학

Unit 1

제1단원

AC Circuit Analysis

교류 회로 분석

KEY TERMS AND CONCEPTS

주요 용어 및 개념

Th&#233venin Equivalent Circuits

finding voltage and impedance in circuit a

The household power distribution system can be simplified with Thevenin's theorem. In this system, distribution lines and transformers form the main network. Electrical appliances can be treated as load impedance, which makes the circuit easier to analyze.

An AC circuit can be split into two parts, circuit A and circuit B, with a single pair of terminals between them. Circuit A can then be replaced by its Thevenin equivalent circuit. That equivalent has a voltage source in series with an impedance.

Replacing circuit A with its Thevenin equivalent does not change the current or voltage of any element in circuit B. The values in circuit B stay the same whether it is connected to the original circuit A or to the Thevenin equivalent. This is why the method is useful for studying connected circuits.

Two values are needed to build the Thevenin equivalent circuit. The first is the Thevenin voltage, which is found from the open-circuit voltage across the terminals of circuit A. The second is the Thevenin impedance, Zt, which is the equivalent impedance of circuit A*.

To form circuit A*, all independent voltage sources are replaced with short circuits. All independent current sources are replaced with open circuits. Then series or parallel impedances can be combined repeatedly to find Zt.

Finding Voltage and Impedance in Circuit A

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key terms and concepts

Learn how Thevenin's theorem simplifies household AC circuits by using open-circuit voltage and equivalent impedance to model circuit A.

Finding Voltage and Impedance in Circuit A | 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

Finding Voltage and Impedance in Circuit A

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