Name: load matching in thevenin circuits
Uploaded: 2024-04-11T12:48:31.000Z
Duration: 1 min 16 s
Channel: JoVE

실제 응용 분야에서 회로는 소스에서 부하로 최대 전력을 전달하도록 설계되었습니다.
Thevenin 등가 회로는 선형 회로가 전달할 수 있는 최대 전력을 결정할 수 있습니다.
전달된 전력은 부하 저항과 전류의 제곱의 곱입니다. 부하 저항이 변함에 따라 달라집니다.
전력을 최대화하는 부하 저항 값을 식별하기 위해 차동 미적분학이 사용됩니다. 이 방정식을 단순화하면 최적의 하중 저항 값을 얻을 수 있습니다.
이 저항 값은 전력의 2차 도함수로 대체되어 음의 값이 되어 최대 전력 조건을 확인합니다.
얻은 저항 값을 통해 최대 전력을 계산할 수 있습니다. 부하 저항이 Thevenin 저항과 일치하지 않으면 전달되는 실제 전력이이 최대에서 벗어납니다.
최대 전력 전달 정리 (Maximum Power Transfer Theorem)에 따르면 부하 저항이 Thevenin 저항과 일치 할 때 가장 높은 전력 전달이 발생합니다.
알려진 값의 두 저항과 연결된 알려진 매개변수의 배터리를 고려하십시오. 배터리의 내부 저항과 일치하는 저항이 최대 전력을 받습니다.

최대 전력 전달

통신과 같은 엔지니어링 분야의 수많은 실제 응용에서는 연결된 부하에 대한 전력 공급을 최적화해야 합니다. 그러나 이러한 추구에는 부하에 공급되는 전력과 동일하거나 이를 초과할 수 있는 고유한 내부 손실이 수반됩니다. 테브난 등가 회로는 선형 회로가 부하에 전달할 수 있는 최대 전력을 찾는 데 도움이 됩니다. 이러한 맥락에서 부하 저항을 조정할 수 있다고 가정합니다.

Figure 1과 같이 부하를 보존하면서 전체 회로를 Thevenin 등가물로 대체함으로써,

<img alt="Figure1" src="/files/ftp_upload/15055/15055_PT_Figure_1.svg" style="text-align: center; height: 140px;">
Figure 1: 최대 전력 전달에 사용되는 회로

부하에 전달되는 전력은 다음과 같이 주어집니다다.

<img alt="Equation1" src="/files/ftp_upload/15055/15055_PT_Equation_1.svg" style="text-align: center; height: 40px;">.................(1)

주어진 회로에 대해 테브난 등가 저항과 전압은 고정되어 있습니다. 부하 저항이 있는 부하에 전달되는 전력의 변화는 부하 저항 값이 작거나 클 경우 작지만 0과 무한대 사이의 일부 부하 저항 값에서는 최대입니다. 최대 전력은 부하 저항이 다음과 같이 표현되는 테브난 저항과 같을 때 발생합니다.

<img alt="Equation2" src="/files/ftp_upload/15055/15055_PT_Equation_2.svg" style="text-align: center; height: 14px;">.................(2)

이는 최대 전력 전달 정리로 알려져 있습니다. 방정식 1과 2를 사용하여 전달된 최대 전력에 대한 표현식을 구하고 다음과 같이 표현합니다.

<img alt="Equation3" src="/files/ftp_upload/15055/15055_PT_Equation_3.svg" style="text-align: center; height: 40px;">..................(3)

이 방정식은 방정식 2가 유효한 경우에만 적용되며, 그렇지 않은 경우 부하에 전달되는 전력은 방정식을 사용하여 결정됩니다. 1.

실제 응용 분야에서 회로는 소스에서 부하로 최대 전력을 전달하도록 설계되었습니다.
Thevenin 등가 회로는 최대 ...

Education

교육

JoVE Core

Electrical Engineering

전기공학

Unit 1

제1단원

DC Circuit Analysis

DC 회로 분석

KEY TERMS AND CONCEPTS

주요 용어 및 개념

Maximum Power Transfer

load matching in thevenin circuits

Load matching in Thevenin circuits helps a source deliver the most power to a connected load. This matters in engineering fields such as telecommunications, where power delivery must be optimized. Even then, internal losses can be significant and may equal or exceed the power sent to the load.

The Thevenin equivalent circuit is a useful way to study this situation. It replaces the full linear circuit with a simpler source and resistance while keeping the load in place. In this setup, the load resistance is assumed to be adjustable, so the power delivered to it can be tested across different values.

For a fixed circuit, the Thevenin equivalent voltage and resistance do not change. The load power changes only a little when the load resistance is very small or very large. It reaches a maximum at one value between zero and infinity.

The maximum power occurs when the load resistance equals the Thevenin resistance. This condition is called the maximum power transfer theorem. Using the load-power equation and this matching rule, the maximum transferred power can be found. If the matching condition is not met, the load power is determined from the general power equation instead.

Load Matching in Thevenin Circuits

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Thevenin Circuit Equivalents

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Load matching in Thevenin circuits helps a source deliver the most power to a connected load. This matters in engineering fields such as telecommunications, where power delivery must be optimized. Even then, internal losses can be significant and may equal or exceed the power sent to the load. The Thevenin equivalent circuit is a useful way to study this situation. It replaces the full linear circuit with a simpler source and resistance while keeping the load in place. In this setup, the load...

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Learn how Thevenin equivalent circuits predict maximum power transfer when load resistance matches Thevenin resistance in linear circuits.

Load Matching in Thevenin Circuits | 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

Load Matching in Thevenin Circuits

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