Name: circuit source symbols and controls
Uploaded: 2024-04-11T12:48:28.000Z
Duration: 1 min 18 s
Channel: JoVE

Le sorgenti in un circuito possono essere indipendenti o dipendenti.
Fonti di tensione o corrente indipendenti forniscono tensione e corrente non influenzate da altri elementi del circuito.
I simboli delle fonti di tensione indipendenti hanno polarità, mentre le sorgenti di corrente indipendenti utilizzano frecce per indicare la direzione della corrente.
Un cortocircuito è una sorgente di tensione indipendente a tensione zero, mentre un circuito aperto è una sorgente di corrente indipendente a corrente zero.
Le sorgenti dipendenti sono generatori di tensione o corrente controllati da altri elementi del circuito. Sono rappresentati da una forma a diamante.
In base alle loro parti di controllo e controllate, le fonti dipendenti sono divise in quattro categorie.
Si consideri un circuito in cui la tensione della sorgente dipendente è controllata dalla corrente attraverso il resistore.
Se un cortocircuito viene aggiunto in serie con il resistore, la corrente di controllo è equivalente alla corrente nel cortocircuito.
Il rapporto tra tensione sorgente e corrente di controllo rappresenta il guadagno della sorgente dipendente.
Allo stesso modo, la tensione di controllo può essere considerata come tensione a circuito aperto.
Quindi, la tensione o la corrente delle sorgenti dipendenti è proporzionale alla tensione o alla corrente di controllo.

fonti indipendenti e dipendenti

Nei circuiti elettrici, le fonti svolgono un ruolo cruciale nel fornire energia per il funzionamento del circuito. Queste fonti possono essere sostanzialmente classificate in due tipi: indipendenti e dipendenti.

Sorgenti indipendenti di tensione o corrente forniscono rispettivamente una quantità fissa di tensione o corrente, che non è influenzata da altri elementi all'interno del circuito. Queste sono rappresentate utilizzando simboli specifici. Le sorgenti di tensione indipendenti sono simboleggiate con polarità (+ e -), che indicano la direzione della differenza di potenziale, mentre le sorgenti di corrente indipendenti utilizzano le frecce per indicare la direzione del flusso di corrente.

Un aspetto interessante delle sorgenti indipendenti è che un cortocircuito può essere considerato come una sorgente di tensione indipendente a tensione zero, perché consente alla corrente di fluire liberamente senza caduta di tensione. Al contrario, un circuito aperto può essere pensato come una sorgente di corrente indipendente a corrente zero, dato che blocca qualsiasi flusso di corrente indipendentemente dalla tensione applicata.

Le sorgenti dipendenti, invece, sono generatori di tensione o corrente i cui valori sono controllati da altri elementi all'interno dello stesso circuito. Negli schemi circuitali sono rappresentate da una forma a diamante.

Queste sorgenti dipendenti sono ulteriormente suddivise in quattro categorie in base alle parti che controllano e da cui sono controllate: sorgenti di tensione controllate in tensione (VCVS), sorgenti di tensione controllate in corrente (CCVS), sorgenti di corrente controllate in tensione (VCCS) e sorgenti di corrente controllate in corrente (CCCS).

Ad esempio, in un circuito in cui l'uscita di tensione di una sorgente dipendente è controllata dalla corrente che scorre attraverso un resistore, se viene aggiunto un cortocircuito in serie a questo resistore, la corrente di controllo diventa equivalente alla corrente nel cortocircuito. Il rapporto tra la tensione della sorgente e la corrente di controllo rappresenta il guadagno della sorgente dipendente.

Allo stesso modo, la tensione di controllo può essere considerata come tensione a circuito aperto. Ciò significa che la tensione o la corrente delle sorgenti dipendenti è proporzionale alla tensione o corrente di controllo.

Fonti Indipendenti e Dipendenti

Le sorgenti in un circuito possono essere indipendenti o dipendenti.
Fonti di tensione o corrente indipendenti forniscono tensione e corrente non influenzate da altri circuiti ...

Education

Didattica

JoVE Core

Electrical Engineering

Ingegneria elettrica

Unit 1

Unità 1

Basics of Electric Circuits

Fondamenti dei circuiti elettrici

KEY TERMS AND CONCEPTS

TERMINI E CONCETTI CHIAVE

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 arrow to show the direction of current flow. A short circuit can be treated as a zero-voltage independent voltage source because it allows current to flow with no voltage drop. An open circuit can be treated as a zero-current independent current source because it blocks current flow even when voltage is applied.

Dependent sources work differently. Their voltage or current is controlled by another element in the same circuit. They are drawn with a diamond shape. There are four types: voltage-controlled voltage sources, current-controlled voltage sources, voltage-controlled current sources, and current-controlled current sources.

The controlling part can be tied to a resistor or another circuit element. For example, if the output voltage of a dependent source is controlled by the current through a resistor, adding a short circuit in series with that resistor makes the controlling current the same as the current in the short circuit. The ratio of the source voltage to the controlling current gives the gain of the dependent source. In a similar way, the controlling voltage can be treated as an open-circuit voltage. This means the voltage or current from a dependent source is proportional to the controlling voltage or current.

Circuit Source Symbols and Controls

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voltage

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circuit terminology

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independent and dependent sources

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...

ohm's law

Resistance and Conductance in Circuits

Resistance and conductance help explain how electric current moves through a circuit. Resistors are basic circuit parts made from metallic alloys or carbon compounds. They are used to model how a material resists current and to control and regulate electrical power in a circuit. Ohm's law describes the link between voltage and current across a resistor. The voltage across a resistor is directly proportional to the current through it. The constant that sets this relationship is resistance.

kirchhoff's current law

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...

kirchhoff's voltage law

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,...

voltage dividers

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...

current dividers

Parallel Resistors and Current Division

Parallel resistors share the same two nodes, so each resistor has the same voltage across it. In this circuit setup, Kirchhoff's current law applies. The source current equals the sum of the currents through each branch. Ohm's law helps find the branch currents from the source voltage and the resistor values. The source current is equal to the source voltage times the sum of the reciprocals of the resistances. This makes it easier to calculate how current divides in the circuit. The current...

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key terms and concepts

Learn how independent and dependent sources work in circuits, how they are drawn, and how control by voltage or current determines dependent source gain.

Circuit Source Symbols and Controls | 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 Source Symbols and Controls

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