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

في التطبيقات العملية ، تم تصميم الدائرة لتوفير أقصى قدر من الطاقة من المصدر إلى الحمل.
يمكن لدائرة Thevenin المكافئة تحديد الطاقة القصوى التي يمكن أن توفرها الدائرة الخطية.
الطاقة المسلمة هي نتاج مقاومة الحمل ومربع التيار. يختلف مع تغير مقاومة الحمل.
لتحديد قيمة مقاومة الحمل التي تزيد من الطاقة ، يتم استخدام حساب التفاضل والتفاضل والتكامل. يوفر تبسيط هذه المعادلة قيمة مقاومة الحمل المثلى.
يتم استبدال قيمة المقاومة هذه بالمشتق الثاني من القوة ، مما ينتج عنه قيمة سالبة ، مما يؤكد شرط الطاقة القصوى.
تسمح قيمة المقاومة التي تم الحصول عليها بحساب الطاقة القصوى. إذا كانت مقاومة الحمل لا تتطابق مع مقاومة Thevenin ، فسوف تنحرف الطاقة الفعلية التي يتم تسليمها عن هذا الحد الأقصى.
وفقا لنظرية نقل الطاقة القصوى ، يحدث أعلى نقل للطاقة عندما تتطابق مقاومة الحمل مع مقاومة Thevenin.
ضع في اعتبارك بطارية من المعلمات المعروفة ، متصلة بمقاومتين لقيمهما المعروفة. تتلقى المقاومة التي تتطابق مع المقاومة الداخلية للبطارية أقصى طاقة.

الحد الأقصى لنقل الطاقة

<div style="direction:rtl">تتطلب العديد من التطبيقات العملية في التخصصات الهندسية، مثل الاتصالات السلكية واللاسلكية، تحسين توصيل الطاقة إلى حمل متصل. ومع ذلك، فإن هذا السعي ينطوي على خسائر داخلية متأصلة، والتي يمكن أن تساوي أو تتجاوز الطاقة الموردة للحمل. تعتبر دائرة ثيفينين المكافئة مفيدة في العثور على الحد الأقصى من الطاقة التي يمكن أن توفرها الدائرة الخطية للحمل. من المفترض في هذا السياق أنه يمكن تعديل مقاومة الحمل.
من خلال استبدال الدائرة بأكملها بمكافئها ثيفينين مع الحفاظ على الحمل كما هو موضح في الشكل1،
<img alt="Figure1" src="/files/ftp_upload/15055/15055_PT_Figure_1.svg" style="text-align: center; height: 140px;"> الشكل 1: الدائرة المستخدمة لنقل الطاقة القصوى  يتم إعطاء الطاقة التي يتم تسليمها إلى الحمل بواسطة <img alt="Equation1" src="/files/ftp_upload/15055/15055_PT_Equation_1.svg" style="text-align: center; height: 40px;">.................(1) بالنسبة لدائرة معينة، يتم تثبيت المقاومة والجهد المكافئين لـ Thevenin. إن تباين الطاقة التي يتم تسليمها إلى الحمل مع مقاومة الحمل يكون صغيرًا بالنسبة للقيم الصغيرة أو الكبيرة لمقاومة الحمل ولكنه أقصى بالنسبة لبعض مقاومة حمل القيمة بين الصفر واللانهاية. تحدث الطاقة القصوى عندما تساوي مقاومة الحمل مقاومة ثيفينين المعبر عنها بـ <img alt="Equation2" src="/files/ftp_upload/15055/15055_PT_Equation_2.svg" style="text-align: center; height: 14px;">.................(2) يُعرف هذا بنظرية نقل الطاقة القصوى. باستخدام المعادلتين 1 و2، يتم الحصول على التعبير الخاص بالقدرة القصوى المنقولة ويتم التعبير عنه كـ <img alt="Equation3" src="/files/ftp_upload/15055/15055_PT_Equation_3.svg" style="text-align: center; height: 40px;">..................(3)
تنطبق هذه المعادلة فقط عندما تكون المعادلة 2 صالحة، وإلا يتم تحديد القدرة المسلمة للحمل باستخدام المعادلة. 1.</div>

في التطبيقات العملية ، تم تصميم الدائرة لتوفير أقصى قدر من الطاقة من المصدر إلى الحمل.
يمكن لدائرة Thevenin المكافئة تحديد الحد الأقصى ...

Education

JoVE Core

Electrical Engineering

الهندسة الكهربائية

Unit 1

الوحدة الأولى

DC Circuit Analysis

تحليل دوائر التيار المستمر

KEY TERMS AND CONCEPTS

المصطلحات والمفاهيم الأساسية

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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maximum power transfer

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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key terms and concepts

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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