Name: ac source conversion in circuit analysis
Uploaded: 2024-04-11T12:48:49.000Z
Duration: 1 min 11 s
Channel: JoVE

考虑一个由电流源以及已知阻抗值的电阻、电容和电感组合构成的电路。
目的是利用电源变换技术来确定电路最右侧支路上的电压降。
利用源变换，可以将一个与阻抗并联的电流源转换为一个与相同阻抗串联的电压源，反之亦然。
通过应用欧姆定律，可计算出电源电压。该值随后可用相量形式表示。
在变换后的电路中，阻抗与电压源以及上支路的另外两个元件串联。由此得到等效串联阻抗。
现在，再次应用源变换技术，将电压源转换回电流源。
接下来，获取新的并联组合的阻抗，并利用该阻抗将电流源重新转换为电压源。
最后，利用分压规则确定最右侧支路上的电压降。

交流电路的源变换

Source Transformation for AC Circuits

频域中的源变换过程需要将与阻抗串联的电压源转换为与阻抗并联的电流源，反之亦然。当交流电路从一种源类型转换到另一种源类型时，必须保持以下关系： <img alt="Equation1" src="/files/ftp_upload/15112/15112_PT_Equation_1.svg" style="text-align: center; height: 16px;"> <img alt="Equation2" src="/files/ftp_upload/15112/15112_PT_Equation_2.svg" style="text-align: center; height: 40px;"> 为了能够确定一个由电流源和电阻器、电容器和电感器的集合所组成的电路中的未知电压（每个电阻器、电容器和电感器都具有不同的已知阻抗），需要执行以下步骤。首先，将电压源转换为电流源，并以此来确定源电流（Ⅰ_s）和阻抗（Z_s）的值。 随后，将电流源转换回电压源时会产生不同的电路。根据该导出电路，需要使用先前确定好的值来计算出源电压(V_s)。最后，通过使用分压规则，则可以识别出位于电阻两端的未知电压。

考虑一个由电流源以及已知阻抗值的电阻、电容和电感组合构成的电路。  
目标是……

Education

教育

JoVE Core

Electrical Engineering

电气工程

Unit 1

第一单元

AC Circuit Analysis

交流电路分析

KEY TERMS AND CONCEPTS

关键术语与概念

ac source conversion in circuit analysis

AC source conversion is a circuit analysis method used in the frequency domain. It changes a voltage source in series with an impedance into a current source in parallel with the same impedance, or it converts a current source back into a voltage source. The source values must keep the correct relationship during each change.

This method helps solve for an unknown voltage in a circuit that includes a current source and components such as resistors, capacitors, and inductors. Each of these parts has a known impedance. The circuit is handled in steps so the final voltage can be found more easily.

First, the voltage source is converted into a current source. The source current, Is, and the source impedance, Zs, are identified. Next, the current source is changed back into a voltage source, which gives a new circuit form. From that derived circuit, the source voltage, Vs, is calculated. The final unknown voltage across the resistor is then found with the voltage division rule.

AC Source Conversion in Circuit Analysis

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Phasors for AC Circuit Analysis

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Phasor Rules for AC Circuit Analysis

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AC Circuit Phasors: Resistor, Inductor, Capacitor

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AC Circuit Rules with Phasor Diagrams

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AC Circuit Response: Impedance and Admittance

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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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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 is a circuit analysis method used in the frequency domain. It changes a voltage source in series with an impedance into a current source in parallel with the same impedance, or it converts a current source back into a voltage source. The source values must keep the correct relationship during each change. This method helps solve for an unknown voltage in a circuit that includes a current source and components such as resistors, capacitors, and inductors. Each of these...

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Norton Current in AC Circuit Analysis

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key terms and concepts

Learn how AC source conversion turns voltage sources into current sources and back again to find unknown voltage with impedance and voltage division.

AC Source Conversion in Circuit Analysis | 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 Source Conversion in Circuit Analysis

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