CircuitJS/C2/LCR-Circuit/English

From Script | Spoken-Tutorial
Revision as of 17:59, 21 November 2023 by Nirmala Venkat (Talk | contribs)

(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to: navigation, search


Visual Cue Narration
slide:1 Welcome to the spoken tutorial on LCR circuit using circuitjs simulator.
Slide 2:

Learning Objective

In this tutorial, we will learn how,
  • A resistor, capacitor and an inductor behave in the AC circuit when connected in series
Slide 3:

System Requirement

To record this tutorial, I am using:
  • Ubuntu Linux 20.04 OS
  • CircuitJS Application
Slide 4:

Prerequisite

To follow this tutorial, you should have a basic knowledge of
  • Electrical circuits
Circuit from the book

LCR Circuit.png

We will make this LCR circuit for demonstration.

Show the diagram To do this experiment, we require,
  • 1 inductor.
  • 1 resistor.
  • 1 capacitor, and
  • 1 AC power supply
Let’s learn to create the same circuit in CircuitJS simulator and understand the concepts.

LCR Circuit

Let us open the circuitJS interface.

In the menu bar, click on File and select New Blank Circuit.

Click on the Draw option

Browse through the menu

Click on Draw menu, and go to Passive Components and select Add Inductor.

Drag and draw the inductor in the work area.

Now we need a capacitor next to the inductor.

Again, go to the Draw menu.

Choose Passive Components and select Add Capacitor.

Drag and draw the capacitor, and place it next to the inductor.

Connect one end of the capacitor to one end of the inductor as shown.

Now we need a resistor in the circuit next to the inductor and capacitor.

Click on the Draw menu, and then select Add Resistor.

Drag and draw the resistor and place it next to the capacitor.

Connect the resistor to the capacitor to form a series connection.

Show the path to find the AC power supply and draw it Next, we need to add the AC power supply.

Click on the Draw menu.

Go to Inputs and Sources, and choose Add A/C Voltage Source (2-terminal).

Drag and place the voltage source above the inductor, capacitor and resistor.

We have all the required components in the work area.

Now let’s connect the components using wires.

Click on the Draw menu and select Add Wire component.

Connect one end of the A/C power supply to the inductor.

And connect the other end of the A/C power supply to the resistor.

Observe the yellow dots indicating the current flow in the circuit.

In large the box at the bottom

Show for all three components

Place the cursor on the resistor component.

You will see its characteristics at the bottom right of the screen.

This block shows the following:
Resistance value, current flow, and voltage through this particular resistor.

Similarly, you can see the characteristics of any component connected in the circuit.

Let us see the characteristics of each component in the LCR circuit with the help of graphs.
Role of resistor component in the LCR circuit.

Highlight one complete sine wave cycle with a box

First, click on the RUN/Stop button to stop the simulation.

Now, right-click on the resistor and select View in New scope option.

Click the RUN/Stop button to start the simulation again.

You will see a graph at the bottom of your screen.

Let us increase the size of this graph for better visibility.

Notice that this is one complete cycle of sine waves.

You can see two lines forming the sine wave on the graph.

Yellow line represents the current flow and green line represents the voltage flow in the resistor.

For the resistor, you can see that the current and voltage lines are in phase.

This means that voltage and current reach their maximum and minimum values at the same time.

The resistor in the circuit limits the flow of current and controls the voltage applied in the circuit.

Role of capacitor component in the LCR circuit.

Highlight one complete sine wave cycle with a box

Now, we will explain the role of capacitors in the circuit.

First, click on the RUN/Stop button to stop the simulation.

Right-click on the graph and select the remove scope option to remove the resistor graph.

Now, right-click on the capacitor and select View in New scope option.

Click the RUN/Stop button to start the simulation again.

After a few sine waves and graph plotting, stop the simulation using the RUN/Stop button.

The green line represents the voltage and the yellow line represents the current in the capacitor.

Notice that the voltage line lags behind the current line by 90 degrees.

That is when the current through the capacitor reaches the maximum value, the voltage is 0.

Hence, the current and voltage flowing through a capacitor are said to be out of phase.

The capacitor in the circuit stores the energy and discharges in a controlled way.

Now, we will explain the role of the inductor in the circuit.

Right-click on the graph and select the Remove scope option to remove the capacitor graph.

Now, right-click on the inductor and select View in New scope option.

Click the RUN/Stop button to start the simulation again.

After a few sine waves and graph plotting, stop the simulation using the RUN/Stop button.

The green line represents the voltage and the yellow line represents the current in the inductor.

Notice that the voltage line is leading the current line by 90 degrees.

That is when the voltage through the inductor reaches the maximum value, the current is 0.

The graphical representation of capacitor and inductor in an LCR circuit is exactly opposite.

The inductor makes sure that the current flow in the circuit remains the same.

In other words, an inductor is used to stabilize the current flow in the circuit.

Slide :

Applications of LCR circuit

LCR circuits are commonly used in
  • Filter designs to selectively pass or stop certain frequencies of an AC signal
  • Radio receivers and transmitters
  • Generating periodic waveforms at specific frequency
  • Sensors such as proximity, pressure and humidity to detect changes in the surrounding values
This brings us to the end of the tutorial.

Let us summarize.

Slide summary In this tutorial, we have learnt how
  • A resistor, capacitor and an inductor behave in the AC circuit when connected in series
Slide :About Spoken Tutorial project The video at the following link summarizes the Spoken Tutorial project.

Please download and watch it.

Slide :Spoken Tutorial workshops The Spoken Tutorial Project Team conducts workshops and gives certificates.

For more details, please write to us.

Slide : Forum for specific questions Please post your timed queries in this forum.
Acknowledgement Spoken Tutorial project was established by the Ministry of Education(MoE), Govt of India
Thank you This tutorial has been contributed by FOSSEE and Spoken Tutorial Project, IIT Bombay.

Thank you for watching.

Contributors and Content Editors

Madhurig, Nirmala Venkat