Name: circuit parts: branches, nodes, and loops
Uploaded: 2024-04-11T12:48:28.000Z
Duration: 1 min 14 s
Channel: JoVE

Электрическая сеть – это система взаимосвязанных элементов, не обязательно образующих замкнутый путь.
В отличие от этого, цепь, также являющаяся взаимосвязанной системой, должна содержать замкнутые пути.
Хотя все цепи являются сетями, не все сети являются цепями.
Исходя из расположения элементов, схема включает в себя ответвления, узлы, петли и сетки.
Ответвление представляет собой двухконтактный элемент, такой как резистор или источник напряжения. Цепь, имеющая источник напряжения, источник тока и два резистора, состоит из четырех ветвей.
Узел соединяет две или более ветвей и представлен точкой. Если короткое замыкание соединяет два или более узлов, они составляют один узел.
Петля — это замкнутый путь, который проходит через несколько узлов, не пересекая ни один узел дважды. Если в цикле есть хотя бы одна ветвь, не общая с другими петлями, он является независимым.
Сетка — это тип петли, в которой нет других петель.
Сеть, содержащая b ветвей, n узлов и l независимых циклов, удовлетворяет фундаментальной теореме топологии сети.

Терминология цепей

Circuit Terminology

Электрическая сеть — это система, состоящая из взаимосвязанных элементов, таких как резисторы, конденсаторы, катушки индуктивности и источники напряжения или тока. В отличие от цепи, электрическая сеть не обязательно образует замкнутый путь. Другими словами, хотя все цепи можно считать сетями из-за их взаимосвязанной природы, не каждая сеть квалифицируется как цепь.

С другой стороны, цепь также представляет собой взаимосвязанную систему электрических элементов, но она должна содержать один или несколько замкнутых путей. Эти замкнутые пути или петли позволяют току течь непрерывно, что делает возможной работу цепи.

Структуру цепи можно разбить на несколько ключевых компонентов: ветви, узлы, петли и сетки. Понимание этих компонентов имеет решающее значение для анализа и проектирования схем.

Ветвь представляет собой отдельный элемент схемы, например резистор, источник напряжения или источник тока, соединенный двумя клеммами. Например, схема, включающая источник напряжения, источник тока и два резистора, будет состоять из четырех ветвей.

Узлы — это точки цепи, где пересекаются две или более ветвей. На принципиальных схемах они обычно обозначаются точкой. Если короткое замыкание соединяет несколько узлов вместе, они фактически становятся одним узлом.

Петля в цепи — это замкнутый путь, который проходит через несколько узлов, не проходя ни одного узла дважды. Петли могут быть независимыми и зависимыми. Независимая петля имеет по крайней мере одну ветвь, которая не используется совместно ни с одной другой петлёй.

Сетка, с другой стороны, представляет собой особый тип петли. Это замкнутый путь, не содержащий внутри себя никаких других петель. Сетки имеют основополагающее значение для определенных типов анализа цепей, таких как анализ сетки, который систематически определяет текущие значения.

Наконец, все эти элементы связаны между собой фундаментальной теоремой сетевой топологии, которая гласит, что для сети, содержащей «b» ветвей, «n» узлов и «l» независимых петель, эти величины связаны определенной формулой, а именно:

<img alt="Equation1" src="/files/ftp_upload/15067/15067_PT_Equation_1.svg" style="text-align: center; height: 14px;" />

Понимание этой взаимосвязи имеет решающее значение для анализа и проектирования электрических сетей и цепей.

Электрическая сеть – это система взаимосвязанных элементов, не обязательно образующих замкнутый путь.
В отличие от этого, цепь, также взаимосвязанная...

Education

JoVE Core

Electrical Engineering

Электротехника

Unit 1

Раздел 1

Basics of Electric Circuits

Основы электрических цепей

KEY TERMS AND CONCEPTS

ОСНОВНЫЕ ТЕРМИНЫ И ПОНЯТИЯ

circuit parts: branches, nodes, and loops

Circuit parts like branches, nodes, loops, and meshes help describe how electrical networks work. An electrical network is a system of connected elements, such as resistors, capacitors, inductors, and voltage or current sources. Unlike a circuit, a network does not have to form a closed path.

A circuit is also made of connected electrical elements, but it must include one or more closed paths. These loops let current flow continuously, which is what makes the circuit operate. Because of this, every circuit is a network, but not every network is a circuit.

A branch is one element of a circuit with two terminals. A resistor, a voltage source, or a current source can each count as a branch. For example, a circuit with one voltage source, one current source, and two resistors has four branches.

Nodes are the points where two or more branches meet. They are usually shown as dots in circuit diagrams. If a short circuit connects several nodes, they act as one node.

A loop is a closed path that passes through several nodes without visiting any node twice. Some loops are independent, which means they have at least one branch not shared with another loop. A mesh is a special loop that contains no other loops inside it.

Meshes are important in mesh analysis, a method used to solve for current values in a circuit. These ideas also connect to the fundamental theorem of network topology. For a network with b branches, n nodes, and l independent loops, these values follow a specific relationship that is important for circuit analysis and design.

Circuit Parts: Branches, Nodes, and Loops

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circuit terminology

Circuit parts like branches, nodes, loops, and meshes help describe how electrical networks work. An electrical network is a system of connected elements, such as resistors, capacitors, inductors, and voltage or current sources. Unlike a circuit, a network does not have to form a closed path. A circuit is also made of connected electrical elements, but it must include one or more closed paths. These loops let current flow continuously, which is what makes the circuit operate. Because of this,...

independent and dependent sources

Circuit Source Symbols and Controls

Circuit sources in electrical circuits can be independent or dependent. They provide the power a circuit needs to operate. Independent voltage sources supply a fixed voltage, and independent current sources supply a fixed current. Their output does not change because of other parts in the circuit. These sources use standard symbols in circuit diagrams. An independent voltage source is shown with + and - signs to mark the potential difference. An independent current source is shown with an...

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Resistance and Conductance in Circuits

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Kirchhoff's Current Law at Circuit Nodes

Kirchhoff's Current Law explains how current behaves at a circuit node. A node is the point where two or more circuit elements meet. The law says the current entering a node equals the current leaving it. That balance follows the rule of charge conservation, which means electric charge is not lost at the junction. When applying KCL, currents entering the node are treated as positive and currents leaving the node are treated as negative. The currents can be added algebraically at the node, and...

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Voltage Balance in Closed Circuit Loops

Kirchhoff's Voltage Law explains how voltage is balanced in a closed circuit loop. It is a basic rule in electrical engineering and comes from the idea of energy conservation. Energy can change form, but it cannot be created or destroyed. KVL states that the algebraic sum of all voltages around a closed path, or loop, is zero. In other words, the total voltage supplied in a loop equals the total voltage drop across the components in that loop. A loop can be traced clockwise or anticlockwise,...

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Series Resistors and Voltage Split

Series resistors split voltage across a circuit. In a series setup, resistors are linked one after another. The same current flows through each resistor in the chain. To analyze this behavior, Ohm's law is used to relate voltage, current, and resistance. Kirchhoff's voltage law says the voltages around a series loop add up to the source voltage. That means the current in the circuit equals the source voltage divided by the total resistance in series. The current value can then be used in Ohm's...

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Parallel Resistors and Current Division

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key terms and concepts

Learn the key parts of circuits and networks, including branches, nodes, loops, and meshes, plus how these terms support circuit analysis.

Circuit Parts: Branches, Nodes, and Loops | 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

Circuit Parts: Branches, Nodes, and Loops

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