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

في دوائر التيار المتردد ، تتميز العناصر السلبية - المقاوم والمحث والمكثف - بجهد الطور والتيار.
المعاوقة هي نسبة جهد الطور إلى التيار وتمثل مقاومة تدفق التيار الجيبي في دائرة التيار المتردد.
بالنسبة لمصادر التيار المستمر ذات التردد الصفري ، يعمل المحرض مثل ماس كهربائى مع مقاومة صفرية ، بينما يعمل المكثف كدائرة مفتوحة ذات مقاومة لا نهائية.
ومع ذلك ، عند الترددات العالية ، يعمل المحرض كدائرة مفتوحة ، ويصبح المكثف دائرة كهربائية قصيرة.
المعاوقة هي كمية معقدة يمكن التعبير عنها في شكل مستطيل ، حيث يشير الجزء الحقيقي إلى المقاومة ويمثل الجزء التخيلي المفاعلة.
يمكن أن تكون المفاعلة موجبة أو سلبية. تعني المفاعلة الموجبة مقاومة حثية ، حيث يتخلف التيار عن الجهد. على العكس من ذلك ، فإن المفاعلة السالبة تدل على مقاومة سعوية ، حيث يقود التيار الجهد.
في الشكل القطبي ، يمكن تمييز المعاوقة بحجمها وزاوية الطور.
يمكن أيضا التعبير عن القبول ، وهو التوافق مع المعاوقة ، في شكل مستطيل ، حيث يمثل المكونان الحقيقي والخيالي التوصيل والاعتراضات ، على التوالي.

المعاوقة والقبول

Impedances and Admittance

<div style="direction:rtl">في عالم دوائر التيار المتردد، تأخذ عناصر الدائرة الخاملة مثل المقاومات والمحاثات والمكثفات طابعًا مختلفًا عندما تتميز بجهد الطور والتيار. يتم التعبير عن سلوكهم من خلال المعاوقة، وهو مفهوم حيوي في تحليل دوائر التيار المتردد. المعاوقة هي مقياس لمقاومة تدفق التيار الجيبي في دائرة التيار المتردد. على عكس سلوكها في دوائر التيار المستمر، حيث تظهر المحاثات كدوائر قصيرة والمكثفات كدوائر مفتوحة، فإن سلوك هذه المكونات في دوائر التيار المتردد يعتمد على التردد. في الترددات العالية، تعمل المحاثات كدوائر مفتوحة، بينما تصبح المكثفات دوائر قصيرة. المعاوقة هي كمية معقدة، جزء حقيقي منها يمثل المقاومة وجزء وهمي يمثل المفاعلة. يمكن أن تكون المفاعلة إيجابية أو سلبية، مما يشير إلى الممانعة الحثية عندما يتخلف التيار عن الجهد، والممانعة السعوية عندما يوصل التيار الجهد. يمكن أيضًا تمثيل المعاوقة بالشكل القطبي، مع تسليط الضوء على مقدارها وزاوية الطور. <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;"> مقلوب المعاوقة هو القبول، والذي يقاس بوحدة سيمنز (S). يمثل القبول السهولة التي يتدفق بها التيار عبر الدائرة. وهو يشتمل على التوصيل (الجزء الحقيقي) والقابلية (الجزء التخيلي). يعتبر القبول، مثل المعاوقة، أداة قيمة في تحليل دوائر التيار المتردد، مما يمكّن المهندسين من فهم ومعالجة الدوائر الكهربائية التي تعمل في ظل الظروف الجيبية.</div>

في دوائر التيار المتردد ، تتميز العناصر السلبية - المقاوم والمحث والمكثف - بجهد الطور والتيار.
المعاوقة هي ...

Education

JoVE Core

Electrical Engineering

الهندسة الكهربائية

Unit 1

الوحدة الأولى

AC Circuit Analysis

تحليل دوائر التيار المتردد

KEY TERMS AND CONCEPTS

المصطلحات والمفاهيم الرئيسية

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

ac-circuit-response-impedance-and-admittance

sinusoidal sources

AC Waveform Basics and Phase

Alternating current, or AC, changes direction and magnitude over time, unlike direct current, or DC, which flows in one direction with constant polarity. AC is the main form of electricity used for modern power transmission and distribution because it can travel long distances efficiently. In homes, power supplies use sinusoidal sources to deliver electricity. A sinusoidal source creates a voltage that rises and falls in a smooth wave-like pattern. This waveform is called a sinusoid, which is...

graphical and analytic representation of sinusoids

graphical-and-analytic-representation-of-sinusoids

Measuring Sinusoid Phase on an Oscilloscope

Measuring sinusoid phase on an oscilloscope helps compare two sinusoidal voltages with the same amplitude and period. An oscilloscope is an instrument used to display and analyze waveforms. The process starts by reading the peak-to-peak value, which is twice the amplitude of the sinusoid. This shows the maximum voltage swing of the waveform. Next, the period and angular frequency are measured. The period is the time for one complete cycle. Angular frequency, often written as omega, is the rate...

phasors

Phasors for AC Circuit Analysis

Phasors are a mathematical tool for analyzing alternating current, or AC, circuits. They represent sinusoids with complex numbers. The phasor magnitude matches the sinusoid amplitude, and the phasor angle shows the phase measured from the positive x-axis. Phasors make AC circuit analysis simpler by removing time from the current and voltage expressions. That lets an AC circuit be treated like its equivalent direct current, or DC, form for calculations. Phasors can also be written in...

phasor arithmetics

Phasor Rules for AC Circuit Analysis

Phasor rules make AC circuit analysis easier by linking sinusoids to their matching phasors. A phasor is a complex-number form of a sinusoidal signal. This connection helps explain how alternating current changes with time. Differentiation and integration work in both the time domain and the phasor domain. If you take the derivative of a sinusoid in time, its phasor is multiplied by jω, where j is the imaginary unit and ω is the angular frequency. If you integrate a sinusoid in time, its...

phasor relationships for circuit elements

phasor-relationships-for-circuit-elements

AC Circuit Phasors: Resistor, Inductor, Capacitor

AC circuit phasors help show how voltage and current behave for resistors, inductors, and capacitors. Phasor representation moves these relationships from the time domain to the frequency domain, which makes AC circuit analysis easier. For a resistor, Ohm's law still applies. The voltage across the resistor and the current through it stay in phase, so their phasors point in the same direction. An inductor works differently because its voltage depends on the rate of change of current. The...

kirchoff's laws using phasors

AC Circuit Rules with Phasor Diagrams

AC circuit analysis uses Kirchhoff's voltage law and Kirchhoff's current law with phasors. In household wiring, AC power from a distribution panel is sent to appliances connected in parallel. These rules help describe how voltage and current behave in sinusoidal steady state. Kirchhoff's voltage law, or KVL, says that the sum of phasor voltages around a closed loop in an AC circuit is zero. The voltages can first be written in the time domain and then changed into phasor form. In phasor...

impedances 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,...

impedance combination

Series and Parallel Impedance Rules

Impedance in series and parallel circuits follows the same rules used for resistors. A string of Christmas lights is a simple example. Each bulb represents one impedance element. In a series connection, the current stays the same through every component. This series behavior matches Kirchhoff’s Voltage Law, or KVL. The total impedance in the circuit is the sum of the individual impedances. The source voltage is then divided among the components based on their values. This is the voltage...

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AC Circuit Node Method in an Angioplasty Model

AC circuit node analysis is used to study an angioplasty system with a catheter turbine. The system helps remove plaque deposits from coronary arteries. Its electrical model is similar to a dual-node RLC circuit driven by a current-controlled voltage source. The analysis begins by collecting the input source voltage, inductance, and capacitance values. These measurements are used to find the driving voltage for the catheter shaft. The circuit is then viewed in the frequency domain, where...

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Impedance Matching with Mesh Currents

Impedance matching in radio communication uses resistor, capacitor, and inductor circuits to help signals move efficiently between a transmitter and a receiver. The circuit must balance the input and output signals before the current in the capacitor can be found. This makes the problem a good example of AC circuit analysis for high school students. The first step is to identify the input voltage and the output signal. The angular frequency is then taken from the time-domain form of the input...

source transformation for ac circuits

AC Source Conversion in Circuit Analysis

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th&#233venin equivalent circuits

Finding Voltage and Impedance in Circuit A

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norton equivalent circuits

Norton Current in AC Circuit Analysis

Norton’s theorem helps simplify complex AC circuits by replacing a two-terminal linear network with a smaller equivalent circuit. That equivalent circuit uses an impedance in parallel with a constant current source. The method lets students break one complicated circuit into two parts and analyze them more easily. To build the Norton equivalent, the source is replaced by its internal impedance. The result is the Norton impedance, which is the same as the Thévenin impedance. This parallel...

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Analyzing Mixed-Frequency Linear Circuits

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Analyzing an Op Amp Audio Filter

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Capacitance Multiplier Circuit for Larger Capacitance

A capacitance multiplier circuit creates a larger effective capacitance from a small physical capacitor. In integrated circuit technology, this approach is useful when a small capacitor is not enough. The circuit can multiply capacitance by as much as 1000, so a 10-pF capacitor can act like a 100-nF capacitor. The design uses two op-amps. The first op-amp works as a voltage follower, which helps isolate the generated capacitance from the loading caused by the second stage. The second op-amp...

key terms and concepts

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

AC Circuit Response: Impedance and Admittance | 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

AC Circuit Response: Impedance and Admittance

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