Name: ac circuit response: impedance and admittance
Uploaded: 2024-04-11T12:48:49.000Z
Duration: 1 min 23 s
Channel: JoVE

W obwodach prądu przemiennego elementy pasywne - rezystor, cewka indukcyjna i kondensator - charakteryzują się napięciem i prądem wskazowym.
Impedancja to stosunek napięcia wskazowego do prądu i reprezentuje rezystancję sinusoidalnego przepływu prądu w obwodzie prądu przemiennego.
W przypadku źródeł prądu stałego o zerowej częstotliwości cewka indukcyjna działa jak zwarcie o zerowej impedancji, podczas gdy kondensator działa jako obwód otwarty o nieskończonej impedancji.
Jednak przy wysokich częstotliwościach cewka indukcyjna działa jak obwód otwarty, a kondensator staje się zwarciem.
Impedancja to wielkość zespolona, którą można wyrazić w postaci prostokątnej, gdzie część rzeczywista oznacza rezystancję, a część urojona reprezentuje reaktancję.
Reaktancja może być dodatnia lub ujemna. Reaktancja dodatnia oznacza impedancję indukcyjną, w której prąd pozostaje w tyle za napięciem. I odwrotnie, reaktancja ujemna oznacza impedancję pojemnościową, w której prąd prowadzi napięcie.
W postaci biegunowej impedancję można scharakteryzować za pomocą jej wielkości i kąta fazowego.
Admitancja, odwrotność impedancji, może być również wyrażona w postaci prostokątnej, gdzie składowe rzeczywiste i urojone reprezentują odpowiednio przewodność i podatność.

impedancja i admitancja

Impedances and Admittance

W obwodach prądu przemiennego (AC) pasywne elementy obwodu, takie jak rezystory, cewki indukcyjne i kondensatory, przyjmują inny charakter, gdy charakteryzują się napięciem i prądem fazorowym. Ich zachowanie wyraża się poprzez impedancję, istotną koncepcję w analizie obwodów prądu przemiennego.

Impedancja to miara oporu, jaki element obwodu stawia przepływowi prądu sinusoidalnego w obwodzie prądu przemiennego. W przeciwieństwie do obwodów prądu stałego (DC), gdzie cewki indukcyjne zachowują się jak zwarcia, a kondensatory jak obwody otwarte, zachowanie tych elementów w obwodach AC zależy od częstotliwości sygnału.

Impedancja to wielkość zespolona, której część rzeczywista oznacza rezystancję, a część urojona reprezentuje reaktancję. Reaktancja może być dodatnia lub ujemna, wskazując na impedancję indukcyjną, gdy prąd opóźnia się względem napięcia, oraz impedancję pojemnościową, gdy prąd wyprzedza napięcie. Impedancja może być również przedstawiona w formie biegunowej, podkreślając jej moduł oraz kąt fazowy.

<img alt="Equation1" src="/files/ftp_upload/15109/15109_PT_Equation_1v2.svg" style="text-align: center; height: 18px;" />

<img alt="Equation2" src="/files/ftp_upload/15109/15109_PT_Equation_2.svg" style="text-align: center; height: 15px;" />

Odwrotnością impedancji jest admitancja, która jest mierzona w siemensach (S). Admitancja reprezentuje łatwość przepływu prądu przez obwód. Składa się z konduktancji (części rzeczywistej) i susceptancji (części urojonej). Admitancja, podobnie jak impedancja, jest cennym narzędziem w analizie obwodów prądu przemiennego, umożliwiając inżynierom zrozumienie i manipulowanie obwodami elektrycznymi działającymi w warunkach sinusoidalnych.

Impedancja i admitancja

W obwodach prądu przemiennego elementy pasywne - rezystor, cewka indukcyjna i kondensator - charakteryzują się napięciem i prądem wskazowym.
Impedancja wynosi ...

Education

JoVE Core

Electrical Engineering

Elektrotechnika

Unit 1

Jednostka 1

AC Circuit Analysis

Analiza obwodów prądu przemiennego

KEY TERMS AND CONCEPTS

Kluczowe terminy i pojęcia

ac circuit response: impedance and admittance

AC circuit response changes with frequency, and impedance describes how resistors, inductors, and capacitors affect sinusoidal current flow. In phasor form, voltage and current are used to show this behavior in a clear way. Impedance is a key idea in AC circuit analysis because it measures opposition to current in an alternating circuit.

These components behave differently in AC than in DC. In DC circuits, inductors act like short circuits and capacitors act like open circuits. In AC circuits, their behavior depends on frequency. At high frequencies, inductors act like open circuits, while capacitors become short circuits.

Impedance is a complex quantity. Its real part is resistance, and its imaginary part is reactance. Reactance can be positive or negative. Positive reactance shows inductive impedance, where current lags behind voltage. Negative reactance shows capacitive impedance, where current leads voltage.

Impedance can also be written in polar form. This form shows both magnitude and phase angle. The reciprocal of impedance is admittance, which is measured in Siemens, or S. Admittance shows how easily current flows through a circuit.

Admittance also has two parts. Its real part is conductance, and its imaginary part is susceptance. Like impedance, admittance helps engineers analyze AC circuits under sinusoidal conditions. It gives another useful way to study and shape circuit behavior.

AC Circuit Response: Impedance and Admittance

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impedances and admittance

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Learn how impedance and admittance describe AC circuit behavior in resistors, inductors, and capacitors, including reactance, phase, and frequency effects.

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electrical engineering

AC Circuit Response: Impedance and Admittance

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