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What is an Embedded System? Definition, Examples, Types & Development

Hello friends, I hope you all are fine. Today, we will discuss What is an Embedded System? We will also have a look at Embedded Systems definition, examples, applications, types & development. For most of you, this term would have been quite familiar & normally people confuse it with a computer or Industrial PC etc. A computer is an application of high-performance Embedded computing but it's not an embedded system itself.

In my article, I am going to tell you all the basic information, need to know about Embedded Systems. What is an embedded system? How is it different from our personal computers? What are its main features? How can we enhance the performance of Embedded Systems? What are the main components of Embedded Systems? What would be the design parameters and constraints in designing an Embedded System? How can we classify such systems? and in the end, I am going to share some common examples.

I have also posted a tutorial on What is Embedded Computer? So, you should also read that because I have shared the basics in it. Moreover, if you are interested in learning Embedded System Programming then you should have a look at 8 Things for Learning Embedded system Programming. Let’s first define a system before diving into embedded systems, because that's essential and without understanding the basics you can't move to the pro.

What is System ???

A system is a group of units, joined together to work in a specific routine and perform some fixed operation.
These units could be of any nature i.e. if you are working on an electronics system then these units will be electronic components.
Similarly, if you are working on some mechanical system then these units will be mechanical equipment or machinery etc.
So, now let's have a look at the embedded systems and see what are its units.

What is an Embedded System ???

What is an Embedded System? In order to understand this question, let's take a simple example of traffic signal lights. "Traffic signal lights" is a simple system, following a fixed routine (i.e. Red, Yellow & Green). Before embedded systems, DLD(Digital Logic Design) was normally used to design such systems using 555 Timer. In DLD circuits, we have to design logic using electronic components (logic gates etc.), which makes the circuit quite messy and thus too difficult to debug. Moreover, DLD circuits are too difficult to upgrade as it involves hardware testing. If you check the image on the right side, I have divided this circuit into 3 blocks:

Green Block: Input Power Supply(battery).
Red Block: Electronics circuitry for Logic Designing.
Orange Block: Output LEDs.

In order to overcome all these DLD issues, embedded systems were introduced where we write the logic in programming code. So, unlike DLD(pure electronics), embedded systems consist of both electronics hardware and programming software. As you can see in the second figure, we are controlling 8 LEDs using a single microcontroller. Now all the logics are written within this microcontroller in the form of programming code i.e. For how long Red LED should remain ON "OR" the duration between lights etc. Now the electronics part is very simple, we can add as many LEDs as we want, we can also change the logic in our software without touching the hardware & most importantly, now we can make it smart by adding cameras or sensors etc.

Embedded Systems Key Features
1	Key Component	Microcontroller/Microprocessor
2	Electronics Hardware	Must (At Least Basic circuit of the embedded controller)
3	Mechanical Hardware	Could be
4	Programming	Must
5	For Microcontrollers	Low-Level Language(i.e. C, Assembly language etc.)
6	For Microprocessors	High-Level Language(i.e. Python, C# etc.)

Let's have a look at a proper Embedded Systems Definition:

Embedded Systems Definition

An Embedded system is a microprocessor/microcontroller based smart system, constituted of both hardware(electronics must) & software(programming) and designed to perform a set of tasks.
It could be a big independent system or a small part of some other system(Embedded or not).

Embedded Controller

An Embedded Controller is a key component of an embedded system, which stores programming code in its ROM(read-only memory) and performs assigned tasks. An embedded controller is of two types:
- Microcontroller: Arduino, PIC Microcontroller, Atmel etc. (Low-Level Programming: Assembly Language, C programming etc.)
- Microprocessor: RaspberryPi, FPGA, BeagleBone, Arduino YUN etc. (High-Level Programming: Python, C++ etc.)
So, we can say embedded systems have their own programmable computer, which we can call embedded computer systems but it's different than general-purpose computers.

A general-purpose computer such as Pentium PC or Intel Industrial PC is not embedded systems as it doesn't perform any specific embedded function. A PC itself is connected to many embedded systems, such as a printer, keyboard, mouse, scanner, modem and many others. Such systems perform specific functions and have their own microcontrollers in them.

Embedded Hardware

In order to power up an Embedded Controller, we need to design an electronics hardware circuit, which we can call Embedded Hardware.
In the case of microcontrollers, we also need to design its electronics basic circuit, to provide operating frequency.
If our embedded system is dealing with complex items i.e. sensors, motors, actuators, solenoids etc., then we have to design their respective control circuits.
Embedded hardware could also be some mechanical structure or hydraulic/pneumatic pumps etc.

In simple words, embedded hardware depends entirely on the nature of embedded systems but it must involve electronics circuitry as we have to power up our microcontroller.

Embedded Software

An Embedded Software is a piece of programming code, has to be uploaded in ROM(read-only memory) of the Embedded Controller & enables the embedded system to perform specific tasks.
Microcontroller companies have also designed windows based software, where programmers can write & compile codes.
For Microprocessor, high-level programming languages are used i.e. python, C#, C++ etc.

Embedded Systems Example

I have written a detailed tutorial on Examples of Embedded Systems, which you should read as I have shared real-life examples of Embedded Systems in it. Let's have a look at a few of them:

Printer

The printer has its own embedded computer system, thus it doesn't need any external controller.
The embedded controller in the printer is programmed to perform few fixed tasks i.e. read the data and print it on paper.

Few other Embedded Systems examples are:

Telecommunication.
Medical Appliances.
Military systems.
Automobiles.
Consumers Electronics.

I hope that by now, you have an idea of what is Embedded Systems? Now let's have a look at key characteristics of an embedded system.

Characteristics of Embedded System

Embedded Systems have few specific characteristics, which you will find in all of them, These Embedded Systems characteristics are as follows:

Specific Function

As I told in the previous section, an embedded system is not a general-purpose system, instead, it's designed to perform specific functions.
If we have a look at embedded system examples (i.e. Camera, Mp3 Player, mobile phones etc.), they are all designed to perform some fixed task(although rich in features).
These specific tasks are installed in embedded systems using programming and once installed, embedded systems keep on doing their assigned tasks.

Specific Algorithm

For performing specific tasks, the algorithm also needs to be specific.
Although in smart embedded systems, Artificial intelligence has changed the game.

User Interface

Embedded systems may or may not have a user interface i.e. GUI (graphical user interface).
In 95% Embedded projects, GUI is available in either hardware(LCD, GLCD, TF etc.) or software(interface to control machines) form.
A user interacts with the embedded system using these user interfaces.

Real-Time Operation

Another characteristic of embedded systems is to operate in real-time.
According to the associated functionality, embedded systems react to events happening in real time and response accordingly.

Multi-Operational

In Embedded systems, multiple operations may occur at the same time at different rates.
For example, obtaining data, processing data, processing audio or video signals etc.
All these operations may occur simultaneously or at different times and at different rates.
Here, I should discuss the MIMO systems, they are multi input and multi-output systems and its opposite is SISO means single-input single output.

Now let's have a look at few features of an Embedded system:

Features of Embedded Systems

These features decide the overall ranking of an embedded system:

Performance

The performance and accuracy of an embedded system is the main feature.
It is measured considering all the conditions and constraints on the system.

Cost

The cost factor is another important feature.
Such systems are built for performing specific functions and in large quantities.
The design process is costly but once a system is designed, customized and produced in bulk, overall cost becomes minimum.

Size

One of the features of an embedded system is its size.
The size should be small and it is done by adding more functionality in a single chip so that the need for external parts is reduced.

Power Consumption

The power consumption is also low.
This feature is becoming more and more important in new systems.
Sometimes it happens that your embedded system has to be isolated and needs to run for a very long time so in such cases the power consumption is a critical factor and it has to be really low.

Reliability

Embedded systems are reliable if they are operated under normal conditions.

These are the features of embedded systems. In the next part of my article, I am going to mention some constraints that should be kept in mind while designing such systems.

Embedded Systems Constraints

There are three constraints on designing of almost every embedded system:

Available System Memory

It is necessary to consider the memory available when designing an embedded system.
So selection of Microcontroller or Microprocessor plays an important role here.
Before starting an embedded system, you must first do the complete calculation of memory usage.

Available processor speed

One of the critical things to look upon is processor speed in the case of embedded systems.
For example, if your task is to calculate the time of some incident then you must select a high speed processor.

Power Dissipation

The need to limit the power dissipation is another constraint.
This is usually done by adding more functions to the CPU.
New designs of high performance embedded processors have more and more functions on a single chip to reduce space and power consumption.
It’s the choice of the user to decide which functions he wants to use.

Now I am moving towards the next section of this article, where I am going to give you an idea of the basic composition of embedded systems.

Embedded Systems Components

Embedded Systems Components can be categorized into four main groups
, which are:
- Analog Components.
- Digital Components.
- Software.
- Converters.

Analog Components

Analog Components are very necessary components as they help in interacting with the real world. Examples of analog components are:

Sensors.
Actuators.
Controllers.

Digital Components

Digital components mostly reside on the chip and do the processing operations. Examples are:

Processors.
Co-processors.
Memory.
Controllers.
Buses.
Application-Specific Integrated Circuits (ASIC).

Converters

Converters are used for converting signals. For example:

Analog to Digital Converter (A2D).
Digital to Analog Converter (D2A).

Software

Without software, an embedded system cannot work. The software is written in both low & high-level languages. This software is burnt to some non-volatile memory i.e. ROM. Examples are:

Application Programs.
Exception Handlers.

So these were the components of an embedded system. Let’s now talk about types of Embedded Systems:

Types of Embedded Systems

There are numerous types of Embedded systems, based on performance and functionality.
Based on performance, there are three types of Embedded systems, which are:
- Small Scale.
- Medium Scale.
- Sophisticated.

On the basis of functionality, Embedded systems types are:
- Real-Time Embedded systems.
- Standalone Embedded systems.
- Networked Embedded systems.
- Mobile Embedded systems.

Let's have an overview of these Embedded Systems types, one by one:

Real-Time Embedded Systems

If an embedded system has to operate for a specific time, without any delay in the output/input, are termed as Real-Time Embedded Systems.
Vehicle Number Plate Recognition using Camera is an example of Real Time Embedded System, such cameras are operating in big cities, they get the plate number using image processing in real-time.
Real-Time Embedded Systems follow time constraints & give output at specific times.
Here's a screenshot of Pixy Camera, which is very small in size, easily interfaceable with microcontrollers/microprocessors and used in real time embedded systems, you can read more about it here: Getting Started with Pixy Camera.

Stand-Alone Embedded Systems

Stand alone embedded system takes input from its own input ports, processes data and gives output.
Such systems work on their own, without using any external host.

Networked Embedded Systems

Networked Embedded System is the fastest-growing type of embedded systems.
These systems are connected with networks that could be LAN, WAN or the internet.
The connection can be wireless or wired.
Such systems use the network to access all the resources.

Mobile Embedded Systems

This is the class of embedded systems that are used in portable devices.
Examples of such devices are mobile phones, cameras, music players etc.

Based on the performance of the microcontroller, there are three types of embedded systems:

Small Scale Embedded Systems

If the microcontroller used in an embedded system is 8 bit or 16 bit, it is classified into a small scale embedded system.
Such systems have less complex hardware and software parts and can also be operated on batteries.
Normally such embedded systems use Arduino boards or PIC Microcontrollers or 8051 Microcontrollers etc.

Medium Scale Embedded Systems

The second class is a medium scale embedded system.
It uses one or more than one 16 bit or 32 bit microcontrollers.
It may use DSP (digital signal processor) or may use RISC (reduced instruction set computer).
The hardware and software of these systems are complex.

Sophisticated Embedded Systems

The third class of embedded systems is sophisticated.
Such systems have huge hardware and software complexity.
So they need PLA (programmable logic array), scalable or configurable processors.
These systems have speed constraints.

That was all about the types and classification of embedded systems. I have discussed the basic information about each type with you guys. I am moving towards the next segment which is on microcontrollers. It is important to discuss why microcontrollers are used with embedded systems. Let’s define a microcontroller first.

Embedded Systems Development

If you ask me who's an Embedded Systems Developer, my reply will be a Mechatronics engineer.
If you want to be an embedded systems developer, you have to learn:
- Electronics Circuits: It's required for interfacing sensors/modules with embedded controllers.
- Embedded Programming: Embedded controllers are trained to specific tasks using programming codes.

Microcontroller

Microcontroller has a CPU as the main part and other parts like RAM, ROM, I/O ports, and timers on a single chip.
You can say that it has all components fixed on one chip.
It is different from microprocessors which have Input/ output ports, timers and other peripherals connected as external parts.
You should also read 10 Things for Choosing Microcontroller as it's gonna help if you wanna select Microcontroller for your Embedded Systems Project.

Microcontrollers are suitable for applications which have limits on size and cost.
The user can not add external devices to such a processor.
No memory could be added.
Few examples of Microcontrollers are Arduino, PIC Microcontroller, 8051 Microcontroller etc.
Microcontrollers are suited for embedded systems.
Other than microcontrollers, field-programmable gate arrays (FPGAs), Application specific integrated circuits (ASIC), custom logic etc. could be used as alternatives.
They come in a variety of types. 4 bit, 8 bit, 16 bit and 32 bit. Mostly 32 bit microcontrollers are used in embedded systems.
The advantages of using microcontrollers are:
- Microcontrollers are efficient.
- They can make use of the same logic to perform many diverse functions.
- Microcontrollers simplify the design of families of products.
- They use more logic to implement functions.
- Microcontrollers now have features that control and minimize power consumption.
Owing to all these advantages and growing development in this field, microprocessors are used vastly.

Now let’s move towards the last segment of this article. I am sharing some applications here.

Embedded Systems Applications

There are a number of areas where embedded systems are used today. Their applications are not limited and it is hard to write all of them here. Embedded Systems are used in areas like:

Automobiles
Telecommunication
Consumer Electronics
Computer
Homes
Offices

Here I am going to give you a list of other applications and examples of embedded systems. They include:

Anti-lock brakes.
Auto-focus camera.
Teller machines.
Automatic toll systems.
Automatic transmission.
Avionic systems etc.

So, that's all about the Embedded Systems and I hope now you can easily understand what is an Embedded System? why and where it is used? You should also have a look at these Embedded System Projects. If you have any questions, regarding this topic then ask in comments and I will try my best to reply them. :)

Introduction to Inverters

Hello friends, I hope you all are well and doing great in your lives. In today's tutorial, I am going to share the Introduction to Inverters. An inverter converts DC voltage or current to AC voltage or current. You can also say that it transfers or converts power from a DC source to an AC load. The aim of this circuit is to supply AC power similar to the one that we receive at homes.

Firstly, I am going to share some basic information related to inverters. In the second section, I will give you the basic configuration or parts of it and in the last section, I will tell you the types and applications. Let's now get started with the Introduction to Inverters:

Introduction to Inverters

An inverter is connected to a DC source and it converts it into AC power in its circuit.

The details on input and output are as under.

The input is DC power. The value of input voltage depends upon the application. Some applications require 12 V while some may require very high voltages of thousands volts.
The ideal output of an inverter is a sinusoidal waveform. Such a wave gives continuous flow of power. But the output from the circuit is generally not ideal. It gives output in the form of square wave, quasi-square wave or PWM.
The conversion of DC power to AC power can be done using two approaches. Both do conversion in two steps.
- In the first approach, a low voltage DC power is converted into high voltage DC power and then in the second step this high voltage DC power is converted to AC power.
- In the second approach, a low voltage DC power is converted to low voltage AC power and then this output is stepped up to high voltage AC power.
They are available in different types in market. They exist in different shapes and sizes. They vary from low power to high power functions.

Let’s move towards the second section in which I am going to tell you all about the main parts of an inverter’s circuit.

Parts of an Inverter

In this section of my article, I am going to tell you about the configuration and constituents of the circuit. The generally used ones may consist of these four parts:

Converter

This is the circuitry to convert commercial power to required DC power.

Smoothing Circuit

This circuit smooths the pulses in DC power.

Inverter

This is the most important part whose purpose is to convert DC to AC power.

Control Circuit

This part controls the entire inverter operation.

In the next section, I am sharing some knowledge on the classification of inverters.

Classification

Inverters can be classified according to a number of different factors.

Output Waveform

First classification is based on the nature of output waveform for example, sine, square, quasi-square or PWM. Inverters can produce a pure sine wave or a modified sine wave. A modified sine wave is the one which is more close to a square wave.

Power Device

Second classification is based on the type of power or switching device used. This power device may be one from transistor, thyristor or MOSFET etc.

Configuration

On the basis of configuration, it can be classified into three types which are given below.

Single Phase Half Bridge

This type of inverters is used in low power applications and also known as inverter leg.
The circuit of single phase half bridge inverter consists of 2 choppers and a DC source with 3 wires.

Single Phase Full Bridge

Full bridge inverters are also used for applications which require low power.
The circuit consists of 4 choppers and a DC source with 3 wires.

Three Phase Inverters

Three phase inverters are used in medium to high power applications.
They provide a three phase voltage source.
It is used where frequency, amplitude and phase of the voltage should be controllable.

Now I am moving towards the last section of this article where I will be sharing some applications of this device.

Applications

Inverters got a variety of applications. I am going to mention some of those.

They are used in AC motor drives with adjustable speed.
They are used in UPS (Uninterruptable Power Supply) which is a very common application now a days.
They are being used in portable devices.

Inverters are used in controlling air flow. For example they are used in fans, blowers and drying machines.
They are used in power generation systems.
Inverters have helped in increasing efficiency of machines and decreasing their sizes. To change speed and other conditions is now easier than before. They are used in driving machine tools, tables, etc.
They also find application in conveyor belts as they can be used for controlling speed.
Inverters are used where there is a need to run AC devices from batteries.
They are used in industries in packaging machines, weighing machines and carts.
They are also used in hybrid and electric cars.
They also find applications in motor speed controllers.
This device is used in voltage compensators.

So, that's all about the Introduction to Inverters. I hope you will get some knowledge from this Introduction to Inverters. Let us know about your questions in the comment section.

Embedded System Projects

Hello everyone, I hope you all are fine and having fun with your lives. Today, I am going to share a detailed Embedded System Projects list for Engineering Students. I hope you guys are gonna enjoy this list of Embedded System Projects. I have shared a lot of Arduino and PIC Microcontroller related projects on my website but they are all posted randomly and are mixed with each other. That's why I have thought of creating this post, so that others can easily access them at one place.

Embedded System Projects are those Projects which are used in almost all kinds of automation. All the modern electronics based projects come in this category. In simple words, all those projects where we use Microcontrollers are termed as Embedded system Projects. So, here I have divided these Embedded system Projects in terms of the Microcontroller used. Before going into the details of these projects, you must first have a look at what is Embedded Systems. If your project is not listed in this list of Embedded System Projects then use the Contact Form and we will reply you. So, here's the detailed list of Embedded system Projects:

Basics of Embedded Systems

Our team has started this section recently and we are sharing the tutorials on basics of Embedded Systems. I will share the links of these tutorials in this section. Let us know if you like these tutorials:

What is Embedded Systems? ? In this tutorial, I have shared the basics of Embedded Systems i.e. what are Embedded System Projects and how to design them, but tis not in details just the basics.
What is embedded Computer? ? In this tutorial, I am going to share the basics of Embedded Computer. If you have read the previous tutorial then you must be well aware of Embedded systems so now its time learn about Embedded Computers.
8 Things for Learning Embedded Systems Programming ? In this tutorial, I have shared the 8 essential things which are required for Learning Embedded Systems Programming.
10 Things for Choosing Microcontroller ? In this tutorial, I have shared the 10 basic things required for selecting the right Microcontroller for your Embedded System Projects.
Real Life Examples of Embedded Systems ? In this tutorial, I have discussed the Embedded Systems Examples and these examples belong to real life. I have shared them in detail.

Arduino Based Embedded System Projects

Below mentioned Embedded System Projects are all designed using Arduino Board. These Embedded System Projects are listed from basics to pro. So, if you are new to Embedded Systems, then I would recommend you to start from the very first project and then move lower but if you are pro then you can find your favorite one from this list of Embedded System Projects.

Circuit Designing of LCD With Arduino in Proteus ? Its first project In this list of Embedded System Projects. In this project, I have interfaced a small LCD with Arduino UNO board and then I have printed words on it. You can use this project to create a simple notice board. Its a good project for beginners.
Interfacing of Keypad with Arduino in Proteus ISIS ? Next thing to learn in this list of Embedded system Projects is Keypad. So, in this proejct we have interfaced Keypad with Arduino. Now you can easily design a small security system where user need to enter password using this keypad and then you print the result on LCD which we learn in previous tutorial.
Intelligent Energy Saving System ? In this Embedded System Project, I have designed an Intelligent Energy Saving System. In this project, the system automatically turns ON or OFF the lights & Fans depending on presence of person in the room. Its YouTube video is also given in this tutorial.
Voice Recognition Project Using EasyVR Shield ? Its a series of tutorials on EasyVR shield and its the first tutorial in this series. In this tutorial, I have given an overview of the Project named as Voice Recognition Project using EasyVR Shield.
Home Automation Project using XBee & Arduino ? In this Embedded System Project, I have designed a complete Home Automation Project in which the Loads of a room are controlled via remote. For wireless communcation between remote and the loads I have used XBee module.
GSM Based Home Security System ? In this Embedded System Project, I have designed a Home Security System and used seven sensors for security purposes and when any of those sensors gave warning then a tet message is sent over to user’s mobile phone.

PIC Microcontroller based Embedded System Projects

Here's the list of Embedded System Projects where I have used PIC Microcontroller as a controlling board. These are not much in number because I have mostly worked on Arduino but still much to have a look. I hope you will like them:

Control Servo Motor with PIC Microcontroller in Proteus ISIS ? Its a simple project in this list of Embedded System Projects, in which I have controlled a Servo motor using PIC Microcontroller. This Servo Motor project can be used in many engineering proejcts where you need rotation.
Interfacing of LM35 with PIC Microcontroller ? Its a digital Thermometer using LM35 and PIC Microcontroller. It will give you the atmospheric temperature in digital form, which you can display on any LCD. Its also a simple beginner level project in this list of Embedded System Projects.
Stepper Motor Control using PIC Microcontroller ? Its a Stepper Motor Control Project in which I have controlled the stepper motor using PIC Microcontroller. Its a medium level project and needs some skills to accomplish it.
Electronic Door Lock using PIC Microcontroller ? Its quite a good project in this list of Embedded System Projects and by adding some more functionalities in it you can make it as a final year project. So, if you have any questions related to this proejct then ask in comments.
Password Protection using PIC Microcontroller ? Its also a good project in which I have designed a simple Password Protection System using PIC Microcontroller. I have given the Proteus Simulations for download on this project link.

8051 Microcontroller based Embedded System Projects

Here's the list of Embedded System Projects where I have used 8051 Microcontroller. I hope you guys are gonna like them, if you have any comments then share them.

I hope you have enjoyed this Embedded System Projects List for Engineering Students. Let me know if you have any other project in mind. So, till next tutorial take care and have fun !!! :)

Wound Rotor Induction Motor

Hi friends, I hope you are fine and having fun. In my last article, we have discussed Squirrel Cage Induction Motor which is a type of 3 Phase Induction Motor. Today, I am going to tell you about a Wound Rotor Induction Motor , which is also a type of 3 phase induction motor. This motor is the one which uses a wound rotor. I will tell about the construction of a wound rotor later in this article. A Wound Rotor Induction Motor is also known as slip ring induction motor.

I will tell you about the construction of Wound Rotor Induction Motor in the first section. In the second section, I would be throwing light on the operation and working principle of Wound Rotor Induction Motor. After that, I will tell you some of the key features and uses of Wound Rotor Induction Motor.

Construction of Wound Rotor Induction Motor

As in other induction motors, the basic parts are stator and rotor. Stator of this motor is the same as the one used in squirrel cage induction motors. Rotor is the part which distinguishes it from other induction motors. Let me give you a brief idea of stator first and then I will tell you about the structure of rotor.

Stator of Wound Rotor Induction Motor

As the name implies, stator is the stationary part of Wound Rotor Induction Motor.
The stator and rotor are separated from each other by a small air gap.
Stator of any type of induction motor is a cylindrical frame inside which rotor rotates.
The cylindrical frame has grooves on its internal periphery to carry electrical circuitry.
The stator winding is excited by AC supply.
That was the basic structure of stator, now let’s talk about rotor.

Rotor of Wound Rotor Induction Motor

In Wound Rotor Induction Motor, the rotor has a 3 phase winding similar to stator winding.
Rotor is also cylindrical in shape and has slots to carry winding.

The winding is placed evenly on slots of the rotor.
are connected to 3 slip rings.
These slip rings are mounted on the shaft.
Each phase is connected to one of the three slip rings. These slip rings are associated with brushes.
The three slip rings rotate with rotor, while brushes remain stationary.
This is all about construction of rotor. Now let’s discuss the working principle.

Working of a Wound Rotor Induction Motor

The working principle of Wound Rotor Induction Motor is as same as in any other induction motor.
AC supply is given to stator winding, which produces a magnetic field that is rotating because of the time changing AC supply.
The flux lines of the magnetic field will cut the rotor and induce an emf according to Faraday’s law.
The induced emf will induce a current that will generate another magnetic field. This magnetic field is called rotor magnetic field.
The magnetic field of stator and the magnetic field of rotor will interact and give rise to a torque which will turn the rotor.

This motor is different because the rotor windings are connected to external resistances through slip rings. The speed and torque can be adjusted in these motors by changing resistance. Now I am going to tell you about some of the key features of these motors.

You may also like to read:

Key Features

Some of the features of wound rotor induction motors are as under:

Speed Control

It is possible to control the speed of such motors. The torque can also be controlled.

High Starting Torque

These motors have high starting torque.

Maintenance

Wound Rotor Induction Motor require more maintenance because of slip rings and brushes.

Cost

Such motors are expensive than other induction motors. The maintenance cost also counts.

Low Starting Current

This motor draws less current at start as compared to squirrel cage induction motors.

Efficiency

Wound Rotor Induction Motor are less efficient than squirrel cage induction motors.

Power Factor

These motors have a low power factor.

Now I am moving towards the last section, in which I am going to tell you all about some of the application areas of Wound Rotor Induction Motor .

Applications

The uses and applications of this induction motor are:

They are used in areas where high starting torque is required. And where squirrel cage induction motors cannot be used because of their high starting currents.
These motors are used with high inertia loads.
Wound Rotor Induction Motor is used in applications which require smooth start and adjustable speed.
Some of the applications of this motor include cranes, mills, hoists and conveyors.
Wound rotor induction motor is also used in fans, blowers and mixers.
They are used in large pumps in water industry.

Squirrel Cage Induction Motor

Hello Friends, I hope you all are fine and doing great. I am here with another article on Induction Motors. In this article I am sharing some basic knowledge on Squirrel Cage Induction Motor. In my previous article named as 3 Phase Induction Motor, I have given a brief overview of this Squirrel Cage Induction Motor.

A 3 phase induction motor has two types based on the rotor construction, named as: Squirrel Cage Induction Motor and Wound Rotor Induction Motor. Former is cheaper and broadly used as it requires less maintenance than later one. Firstly, I am going to tell you about the structure of squirrel cage induction motor. Afterwards I will cover the working principle and features of Squirrel Cage Induction Motor. In the last sections, I will share some advantages and uses. In simple words, the type of 3 phase induction motor which uses a squirrel cage rotor is called squirrel cage induction motor.

Construction of Squirrel Cage Induction Motor

All induction motors have a rotor and a stator. Basically, it is the construction of rotor which makes Squirrel Cage Induction Motor different from Wound Type Induction Motor. Stator is same in both types of motors. Let’s first talk about stator of Squirrel Cage Induction Motor:

Stator of Squirrel Cage Induction Motor

Stator is that component of motor which is stationary.
It is the outer most frame in which rotor is placed.
It has grooves on internal circumference to carry electric circuitry. This circuitry is excited by 3 phase supply.
The 3 phase winding circuit is placed on the slots. These winding are 120 degrees apart connected as star or delta configuration.
Now let’s move towards the construction of rotor.

Rotor of Squirrel Cage Induction Motor

Rotor is the rotating part of a motor. It contains a cylindrical core.
The rotor core is made in lamination to reduce eddy currents.

Squirrel cage type rotor consists of bars of copper that we call conductors.
The copper bars or conductors are longer than the rotor and are fixed in grooves of rotor core.
These extended conductors are short circuited with each other by means of copper rings on each sides.
Also rotor is sometimes provides with fans on each side for cooling purposes.
This type of construction of bars and end rings is similar to a squirrel cage on which it is named.
That was all about rotor construction. Other than rotor and stator, a motor has also other parts to support and protect the assembly.

You may also like to read:

Working of a Squirrel Cage Induction Motor

In this section, I will share the working of a squirrel cage induction motor with you guys.

When the winding of stator are given a 3 phase AC supply, a current will start flowing through it.
This 3 phase AC will give rise to a rotating magnetic field in the rotor.
The speed of rotation of this magnetic field can be found from the frequency of AC supply and number of poles.
This speed is the synchronous speed of motor.
The rotating magnetic field of stator will induce voltage in rotor because its flux lines cut through the rotor. This induced voltage will induce current in rotor winding and another magnetic field will be generated which is rotor’s magnetic field.

As you all know, that a current carrying conductor experiences a force on it in presence of a magnetic field. The rotor will also experience a force which would start turning it. This force will produce a torque and rotor will rotate.

Key Features

Now I am mentioning some important features of a squirrel cage induction motor. I will talk about speed, starting current, direction of rotation, slip and power factor. First on the list is speed.

Speed

A squirrel cage induction motor generally operates at a constant speed. This speed is synchronous speed.

Starting Current

Such motors require high starting currents. Which may result in fluctuations in voltage.

Direction of Rotation

The direction of rotation of these motors can be reversed if you interchange two power lines out of three.

Slip

As for other induction motors, the slip is defined as the difference in speed of rotating magnetic field of stator and rotating speed of rotor. The speed of rotation of magnetic field is called synchronous speed. Slip is expressed as a ratio with synchronous speed or in percentage.

Power Factor

Power factor is the ratio of actual power to apparent power. It is expressed in percentage. The power factor is low when motor is running at no load and it is high when motor is operating at full load.

Advantages

In this part, I will tell you guys some of the advantages of squirrel cage induction motor.

Squirrel cage induction motors are:
- Cheap
- Robust
- Rugged
- Require less maintenance
Due to cage structure of rotor, they require less material. So copper losses decrease.
Due to absence of brushes, the chances of spark are reduced.
These motors are provided with fans, so less heat is generated.

Now I am moving towards the last segment of my article, where I will tell you some of the uses of squirrel cage induction motors.

Uses

This type of motor finds its uses in industries because of their cost. They are extensively used in industrial applications instead of wound type induction motor. They are used in applications where low starting torque is needed. Such motors may also be used as generators.

Introduction to Synchronous Motor

Hi friends, hoping everyone is fine and enjoying their lives. I am here today with an article on Introduction to Synchronous Motor. You all already know that motor is a mean of converting electrical energy into mechanical energy. Synchronous motor is the type of motor in which the rotating speed of rotor is same as the rotating speed of magnetic field. In other words, rotor rotates at the synchronous speed unlike Induction Motor, which we have discussed in Introduction to Induction Motor.

In this article, I will share the Introduction to synchronous motor with you guys. First things first, I am telling you about its construction and working in first two segments of my article. While later I would be throwing some light on its key features followed by methods of starting and areas of application. So, let's have a look at Introduction to Synchronous Motor:

Construction - Introduction to Synchronous Motor

In Introduction to Synchronous Motor, we will first talk about the construction of synchronous motor.
Talking about its construction, the basic structure is same as of other motors.
Stator and rotor are the main parts while frame is the cover.
Stator and rotor both make up the electric and magnetic circuitry of Synchronous motor.
I will tell you about the stator first:

Stator of Synchronous Motor

As the name suggests, stator is the stationary part of motor.
It is the outer frame which is cylindrical in shape.
This cylindrical frame is laminated and has slots to carry winding circuitry
Stator of this motor is supplied 3 AC power.
The winding circuit of stator is called stator winding.

Now, I will tell you about the rotor of a synchronous motor.

Rotor of Synchronous Motor

Rotor is the rotating part, which rotates exactly at the same speed as the stator magnetic field.
It is also cylindrical in shape and it is the shaft of the motor from where output load is connected.
It rotates in the stator frame which is separated by an air gap.
Rotor of a synchronous motor is excited by a DC source.

Frame of the motor protects and cover the whole assembly. It can either be built in vertical or horizontal shape and the type of covering depends on its area of use. That was all about construction of a synchronous motor. The next on my list in Introduction to Synchronous Motor is working principle and operation of this motor.

Working of Synchronous Motor

Let’s now talk about the working of these motors briefly. The operation of a synchronous motor is basically that the rotor tries to follow the rotating magnetic field of stator and rotates at a speed approaching to it. This motor is a doubly excited machine. The rotor winding is excited by a DC source while the stator winding is excited through an AC source. A 3 phase rotating magnetic field is produced by stator winding due to 3 phase AC. And a constant magnetic field is produced by rotor winding.

At some instant of rotation, the poles of two magnetic fields may attract each other while at some other instant, they repel each other. The rotor will not start rotating due to these interactions due to its inertia. So an external mean will compensate and provide initial rotation to the rotor. Once the rotor starts moving at the synchronous speed, this external source is shut off.

In synchronous motor, the magnetic field of rotor is produced not by the magnetic field of rotor through induction. Instead the magnetic field is generated by direct current supply. Therefore, the air gap between rotor and stator is not kept very small as in the case of induction motors. Next thing in Introduction to Synchronous Motor is the important features of this motor.

Key Features of a Synchronous Motor

In this segment of my article, I am sharing some features of this type of motor which differentiates it from other motors.

Speed

Generally, the speed of ranges from 150 rpm to 1800 rpm. The speed remains constant from no load to full load and can be found from the following formula:

N_s = 120 * f / p

Where f = frequency of AC supply

p= no of poles

The speed is synchronous speed. It does not depend on load conditions.

Starting Torque:

Synchronous motors need some external method for starting as it has no starting torque. The next section of this article gives the commonly used methods to start it.

Rating

The power rating of synchronous motors is 150kW to 15MW.

Efficiency

Synchronous Motors are highly efficient machines. Their efficiency is much greater than induction motors.

Cost

Synchronous motor is costly as compared to induction motor of same rating.

Power Factor Correction

Synchronous motors have a leading power factor therefore used in areas where power factor correction is needed.

Maintenance

This motor uses brushless excitor which decreases the maintenance problem of this machine.

Now, I am moving towards last two parts of this Introduction to Synchronous Motor, where I am going to share some knowledge about the methods of starting and uses of these motors.

Methods of Starting a Synchronous Motor

As I told you earlier in my section on key features, synchronous motor cannot self start as it has no starting torque. Therefore to overcome this problem different ways are used. Some external mean is used at start for bringing up the speed up to synchronous speed. The three main ways are as under:

Reducing frequency of stator to a safe starting level.
Using external prime mover.
Using damper windings.

These are the ways which are used to start a synchronous motor.

Uses and Areas of Application

Introduction to Synchronous Motor won't be complete unless we have a look at its uses and areas of Application, I am sharing some of the uses of synchronous motor which are given below.

The basic use of a synchronous motor is “power factor correction” that means to increase the power factor of a system.
Synchronous motors are also used in voltage regulation. For example, they are used at the end of transmission lines to regulate voltage.
Synchronous motors are commonly used for low speed, high power loads. Their application area is constant speed constant load drives.
With VFD (variable frequency drive), synchronous motors are used to attain a range of speeds.
Synchronous motors are used in air and gas compressors and vacuum pumps.
They are also used in blowers, exhausters and fans.
Such motors also find their application in crushers, mills and grinders.

So that's all about the Introduction to Synchronous Motor and I hope you have enjoyed it. I will surely gonna post more tutorials on Synchronous Motor. So, take care and have fun !!! :)

3 Phase Induction Motor

Hi fellows! Hoping everyone is fine and doing great. Today, I am going to write about 3 Phase Induction Motor. As I mentioned earlier in my article on Introduction to Induction Motors, there are two types of Induction Motors, Single Phase Induction Motor and 3 phase Induction Motor.

3 phase induction motor is the one which operates on three phase AC supply. It is the most commonly used motor for high load and industrial applications. I would discuss advantages of a 3 phase induction motor later in this article. Three phase induction motors are further divided into two types; Squirrel Cage Induction Motor and Wound Rotor Induction Motor based on the construction of rotor. First of all, I am going to discuss about the construction of 3 Phase Induction Motor and then I will throw some light on its working.

Construction of 3 Phase Induction Motor

Talking about its construction, like any other motor a 3 phase induction motor consists of a rotor and a stator. Let’s revise the basic knowledge about rotor and stator first.

Rotor is the rotating part while stator is the stationary part of motor.
Rotor is separated from the stator by a small air gap.
Stator is actually a cylindrical frame inside which the cylindrical core of rotor rotates.
The stator of motor has slots on its internal side to carry the winding circuitry. This circuit is supplied with AC power. This winding is called stator winding.
As I told earlier, rotor is a cylindrical core which is laminated and it acts as the output shaft of motor.
Rotor of motor has also slots to carry conductors. These conductors make up rotor winding.
Now, I am going to discuss types of rotor.

Types of a 3 Phase Induction Motor

Based on the rotor construction, a 3 phase induction motor is further classified into two types:

Squirrel Cage Induction Motor
Wound Rotor Induction Motor

Squirrel cage induction motor is cheaper than wound type, and because of the absence of brush assembly it requires less maintenance due to less wear problems.

Squirrel Cage Induction Motor

First I will talk about squirrel cage type of induction motor.
The rotor of a squirrel cage type motor consists of bars of copper.
These copper bars or conductors extend out from the rotor length and are fixed in slots of rotor core.
The bars which are extended out are short circuited together by means of copper rings on each sides as shown in figure.
This type of construction of bars and end rings is similar to a squirrel cage, from where the name comes. Next is the construction of a wound type induction motor.

Wound Rotor Induction Motor

In wound rotor induction motor, there is a 3 phase winding which is similar to stator’s winding.
This winding is placed uniformly on slots of the rotor.
The endings of these windings are connected to 3 slip rings on the shaft.
Each phase out of three phase is connected to one slip ring.
The slip rings of each phase rotate with rotor and are further associated with brushes which are stationary. The construction is shown in figure.
That’s all about construction and classification of 3 phase induction motor. Now let’s discuss about working principle.

Working Principle of 3 Phase Induction Motor

In this section of the article, I am going to talk over the working principle and operation of a 3 phase induction motor. Before diving into the details, let’s revise some basic concepts and laws that govern its operation.

Faraday’s Law:

Faraday’s law is the basic law of electromagnetic induction which plays the most important part in the working of a 3 phase induction motor.
According to which an emf is induced in a conductor when it is placed in a varying magnetic field or if the conductor is rotated in a magnetic field. In other words, emf is induced whenever there is a relative motion of the conductor and magnetic field.
Also, if the conductor is a closed circuit, a current is produced termed as induced current.

Lenz’s Law:

Following Faraday’s Law as explained earlier in the previous point, when an emf is generated in a conductor, its polarity would be such that it will produce current whose magnetic field will oppose the change that is producing current. This is called Lenz’s law.

Lorentz Force:

Lorentz force is the force which is responsible to move the conductor in the magnetic field.
Whenever, a current is flowing in a conductor in the presence of a magnetic field, the conductor will experience this force.

That was all about the basics, now I am going to throw light on its working and development of torque.

First of all, a 3 phase AC voltage is supplied to the stator windings due to which a 3 phase current starts flowing in it. These currents flowing in windings will produce a magnetic field that rotates due to AC oscillations. Now, the flux of this rotating magnetic field will cross the rotor conductors and a voltage is induced in them which depends on three factors; the relative speed of conductor and magnetic field, magnetic flux density and length of the conductor. The result of this induced voltage is the generation of induced current in rotor, which lags behind the rotor’s induced voltage. This leads to the production of rotor’s magnetic field. Finally, the torque induced is the scaled product of stator magnetic field and rotor magnetic field and the rotor of 3 phase induction motor starts rotating.

The rotor of induction motor never achieves the synchronous speed to keep itself rotating as I discussed in my article on Induction Motors. Next, I am going to give some equations and formulas for calculating synchronous speed, slip and rotor frequency of 3 phase induction motor.

Let’s first talk about Synchronous speed. Synchronous speed is the speed of rotating magnetic field of stator. It is represented as n_s. If “f” is the frequency of AC supply and “p” is the number of poles then n_s = 2*f/p.
Second term on the list is slip of induction motor. Slip is denoted by “p” and it is the difference of synchronous speed and rotors mechanical speed. If synchronous speed is n_s and rotor speed is n_r then s = (n_s - n_r). Slip is also expressed as a ratio per unit or as percentage of synchronous speed. This expression is used to find rotor speed, when slip of motor is known.
Rotor frequency is also discussed for 3 phase induction motors. This frequency is directly proportional to the slip. Represented by f_r, it is expressed by the following formula: f_r = s * f

That was all about the working of a 3 phase induction motor, so before telling the advantages I am going to give a brief idea on its equivalent electric circuit.

Equivalent Circuit of a 3 Phase Induction Motor

A 3 phase induction motor is also called a rotating transformer as working principle of both are quite similar. So, the equivalent circuit is also similar to that of a transformer as shown in image. Right side of the image shows rotor circuit and left side is stator side.

On the stator side, there is resistance and self-inductance in stator windings. R1 is the resistance of stator and X1 is stator reactance.
E1 is the stator voltage. Er is the induced voltage in rotor windings while Vp is the applied voltage to the machine.
On the rotor side, Rr is the rotor resistance and Xr is the rotor reactance.
A_eff denotes the turn ratio of a transformer which associates E1 and Er.
Xm is the magnetizing reactance.
I1 is the stator current while Ir is the current in rotor.

In the last section of my article, I am gonna give some advantages of a 3 phase induction motor.

Advantages

Let’s now take a look on the advantages of a 3 phase induction motor.
3 phase induction motors are simple and require easy maintenance.
They are preferred because of low price.
They can be used in rugged environments.
A 3 phase induction motor is brushless so the problem of maintenance and wear is avoided.
Speed of this motor can also be controlled.

Single Phase Induction Motor

Hi friends, I hope you all are fine and doing great with your lives. Today, I am gonna give you an Introduction of a Single Phase Induction Motor. As I previously mentioned in my article on Introduction to Induction Motors, there are two main types of Induction Motors, single phase induction motor and 3 phase Induction Motor. For information on three phase, you can read my article on 3 Phase Induction Motors. Now let’s talk about the definition of single phase induction motor.

A single phase induction motor is the one which operates on a single phase AC power source. This motor is used in the applications where requirement of power is low. It is generally used in domestic applications because of limited size and less power. Some of the uses include fans, washing machines, pumps, toys, vacuum cleaners, refrigerator compressors and in machine tools.

First I will tell you about its construction, followed by working principle and advantages. And in the last sections of this article, I will share some knowledge about the starting problem of a single phase induction motor and give a comparison of 3 phase and single phase induction motors. Let’s now take a look on construction of a single phase induction motor.

Construction of Single Phase Induction Motor

The basic construction of Single Phase Induction Motor is similar to all other motors.
A rotor and a stator are the two main components of Single Phase Induction Motor.

We will have a look at both Stator and Rotor one by one below.
So, first of all have a look at the functionality of Stator of Single Phase Induction Motor:

Stator of Single Phase Induction Motor

The stator of a single phase induction motor is the stationary part as in other motors.
The stationary stator of the motor is supplied with an AC power supply which is single phase.
Stator is a cylindrical frame having slots.
Inside the stator frame, cylindrical core of rotor is placed with a little air gap in between them.
The purpose of making slots is to carry winding circuit.
The winding circuitry of stator is called stator winding which in the case of this particular motor is single phase.

You may also like to read:

Rotor of Single Phase Induction Motor

The second basic part of motor is the rotor.
As in all other motors, the rotor is the rotating part.
Rotor is cylindrical in shape and it is connected to the output shaft of the motor.
In other words, this is the part which supplies rotation at the output. Load is connected to the shaft of rotor.
Rotor of a single phase induction motor is similar in construction with a squirrel cage 3 phase induction motor. I have explained its construction in my article on 3 phase induction motor.
Rotor has slots on all over its surface to carry conductors that are copper or aluminum bars.
These conductor bars are short circuited with each other by two end rings. One end ring is on each side of rotor.
Just like rotor of a squirrel cage 3 phase induction motor, it has no slip ring and brush assembly.
That was all about basic structure of stator and rotor, now I am moving towards next section of this article.

Working of Single Phase Induction Motor

The working principle of a single phase induction motor is based on Faraday’s law of electromagnetic induction. AC supply is given to stator windings which is single phase, the current flowing through the winding will produce a magnetic field which is called stator magnetic field. The flux lines of this magnetic field will cross the conductors of rotor. As the flux is changing due to changing magnetic field of AC supply with time, an emf and current will be induced in the rotor. The induced current will give rise to another magnetic field which is called rotor magnetic field. A single phase induction motor differs in operation from a 3 phase induction motor in the sense that this motor cannot generate a rotating magnetic field. Instead of a rotating magnetic field, it produces a magnetic field which pulsates due to AC oscillations between 0 and 180 degrees. In other words, the magnetic field does not rotates but reverses 180 degrees. The interaction of the two magnetic fields or magnetic fluxes, one from stator and second from rotor will produce torque.

Advantages of Single Phase Induction Motor

In this section, I am highlighting some of the advantages of a single phase induction motor which are as under.

A single phase induction motor is more economical where less power is required.
Such motor is simple in construction because of absence of slip rings and brushes.
Because of simple construction, it is very easy to maintain and repair.
This motor is cheap in cost.
Also, single phase induction motors are reliable and robust.

Starting Problem of a Single Phase Induction Motor

The initial torque or starting torque of a single phase induction motor is very low so this motor cannot take a self start. For 3 phase induction motor the starting torque is high so it can start on its own. Now to overcome this starting problem, capacitor can be used to build the starting torque. This capacitor creates a phase difference between the flux of rotor and flux of stator. The capacitor is used with a starting winding which is switched off once the motor is started.

Comparison of Single Phase and 3 Phase Induction Motors

In this segment of my article, I am going to give a little comparison of single phase and 3 phase induction motors so you can get an idea which one is best for your application. Both are compared on the basis of their features, construction, supply and uses.

The output produced by a single phase induction motor is about half as produced by 3 phase induction motor.
A single phase induction motor is used where less power is required as compared to 3 phase induction motor.
The efficiency and power factor is also low in case of single phase induction motor.
Single phase motors are simple and cheaper for small rating as compared to 3 phase induction motors.
Starting torque is low in single phase motor as compared to 3 phase induction motor.
Single phase induction motors are used for domestic applications while 3 phase induction motors are used in industrial applications.
Maintenance of a single phase motor is very easy in contrast with 3 phase induction motor.
Another important point is the construction. It’s easy to construct a single phase induction motor as compared to 3 phase induction motor.
Single phase induction motor is reliable and economical if compared to 3 phase induction motor.
3 phase induction motor is self starting while single phase induction motor is not a self starting motor.

Introduction to Induction Motor

Hi fellows! Hoping everyone is fine and doing great. Today, I am going to give you an Introduction to Induction Motors, the term which is very common and familiar but still many of us do not know it’s working and difference from other motors. Induction Motor is an AC electric motor, having a stator and a rotor just like other motors, but the working principle is a little different which would be discussed further. There are two types of Induction Motors, one is named as Single Phase Induction Motor, while the second one is named as 3 Phase Induction Motor.

An Induction motor is also called asynchronous motor, because the speed of rotation of its rotor is less than stator. In other words, it does not run at its synchronous speed. Before going into the details of the working principal of induction motor, I wanna first summarize the basic concepts of Rotor and Stator:

Rotor

Rotor is the rotating part of the induction motor, which is actually the shaft of the motor.
Rotor of an Induction motor is a laminated cylindrical core.
Moreover this laminated cylindrical core has slots that carry aluminum or copper conductors, which are joined at ends.
So, let's now have a look at the stator of the induction motor.

Stator

In the previous section, we have discussed the rotor details, now I am gonna throw some light on stator.
Unlike rotor, stator is the stationary part of the induction motor.
While rotor is a small cylindrical core which rotates in the outer cylindrical frame of the motor. This outer cylindrical frame is named as stator.
Stator has slots to carry the winding circuit which is supplied by an AC power.

Both stator and rotor are made up of an electric circuit to carry current and a magnetic circuit to carry magnetic flux. You may also like to read:

Working of Induction Motor

The working of an Induction Motor can be summarized as, “the stator winding produces magnetic field and due to electromagnetic induction a current is induced in rotor which produces torque”. No electrical connection exists between rotor and stator which differentiates it from other motors (DC, Synchronous), as it works on Faraday’s law of Electromagnetic Induction. The AC power supplied to the stator creates a magnetic field which is changing over time due to AC oscillations. This changing magnetic field produces changing magnetic flux that induces a current in rotor windings in accordance with Faraday's law. This current will generate a magnetic field to oppose the stator magnetic field in accordance with Lenz’s law. To oppose this change, the rotor will start rotating in the direction of changing magnetic field of the stator. Relative speed of the stator’s magnetic field and rotor is the driving factor. Therefore, the speed of rotor is always maintained less to keep it moving.

Let’s take a look on some parameters of an Induction Motor like poles, synchronous speed, slip and power factor.

Poles

Number of poles of an induction motor is denoted by “p”.
A single phase AC machine has 2 poles of opposite polarity set at 180 degree apart.
A simplest 3 phase machine has 6 poles which are set at 60 degree apart.

Synchronous Speed

It is the speed of rotation of stator’s magnetic field denoted by “n_s”.
n_s= 2f/p

Where, f = frequency of AC supply p = no. of poles

Slip

Slip is the difference between stator's magnetic field and rotor's mechanical speed of the induction motor.
We can also say that its the difference between synchronous speed and operating speed. expressed as a ratio.
s=(n_s-n_r)/n_s

Power Factor

The power factor of a motor is the ratio of real power to the apparent power.
At full load power factor of an induction motor ranges from 0.85 to 0.90 and at no load it is approx. 0.12.

Types of Induction Motors

Now lets just take a brief look on types of induction motor. Single phase and three phase are the two types of an AC Induction Motor. Single phase motors are used for smaller loads while 3 phase motors are used in high load applications.

According to the type of rotor, an induction motor is divided into two types; squirrel cage and slip ring /wound type motor. The most commonly used is the squirrel cage induction motor. Concluding, Advantage of Induction Motor is its simple operation, reliability and low cost. It is used in a number of applications in home appliances and commercial uses such as pumps, compressors, fans, mixers, conveyors, crushers, machine tools, cranes, etc.

Line Following Robot using Arduino

Departments:

Components:

Sensors:

IR Sensor

Microcontrollers:

Arduino Uno

Codings:

Arduino C

Softwares:

Hello everyone, I hope you all are fine and having fun with your lives. Today, I am going to share a very basic project named as Line Following Robot using Arduino. I have designed a three wheeler robot and have placed IR sensors beneath it to detect the black line and then I have made it move over this Black Line.

This Line Following Robot is not doing any extra feature i.e. turning or rotating back. It will just simply move in the straight line. I have also posted a short video at the botton of this tutorials which will give you better idea of how this robot moves. You should first read this tutorial and design the basic robot and once you are successful in designing the basic Line Following Robot then you should have a look at my recent Project Line following Robotic Waiter in which I have designed a Robotic waiter which follows the line and also take turns on different tables. So, let's get started with Line Following Robot using Arduino.

Line Following Robot using Arduino

First of all I have designed the Mechanical model of the robot, which has three wheels on it.
Its a triangular method in which the motors were attached to the front two wheels and the back wheel is a caster wheel, which is present in the middle of the robot.

Here's the image of front wheel coupled with the DC Gear Motor:

Now let's have a look at the rear caster wheels, shown in below image:

Finally, I have used Acrylic as the body of the robot.
Here's the assembled version of our Line Following Robot:

Now that we have the mechanical design of our robot and we have assembled it completely.
So, now comes the electronics part where we are gonna place the DC Motor Driver Circuits and will also place the IR sensors.
I have used Arduino board for programming of this Line following Robot.
First of all, I have designed the 2 relay baord for DC motors.
Its circuit diagram is shown in below figure:

We also need a voltage divider circuit because we need such a power supply from which we can get 5V, while our source battery is of 12V.
So, in order to do that I have used 7805 Regulator IC and have designed a simple circuit as shown in below figure:

Now placing all the components over the Line following Robot, it looked like something as shown in below figure:

Here's the Arduino code which you need to upload in your Arduino board:

#define motorL1 8
#define motorL2 9
#define motorR1 10
#define motorR2 11

#define PwmLeft 5
#define PwmRight 6

#define SensorR 2
#define SensorL 3
#define Sensor3 A0
#define Sensor4 A1

#define TableA A4
#define TableB A2
#define TableC A5
#define TableD A3

int OriginalSpeed = 200;
int TableCount = 0;
int TableCheck = 0;
int RFCheck = 10;

void setup() 
{
  Serial.begin (9600);
 
  pinMode(motorR1, OUTPUT);
  pinMode(motorR2, OUTPUT);
  pinMode(motorL1, OUTPUT);
  pinMode(motorL2, OUTPUT);
  
  pinMode(PwmLeft, OUTPUT);
  pinMode(PwmRight, OUTPUT);
  
  pinMode(SensorL, INPUT);
  pinMode(SensorR, INPUT);
  pinMode(Sensor3, INPUT);
  pinMode(Sensor4, INPUT);
  
  pinMode(TableA, INPUT);
  pinMode(TableB, INPUT);
  pinMode(TableC, INPUT);
  pinMode(TableD, INPUT);
  
  MotorsStop();
  
  analogWrite(PwmLeft, 0); 
  analogWrite(PwmRight, 0);
  delay(2000); 
 // Serial.println("fghfg");
  
}

void loop() {
  MotorsForward();
  PIDController();
}

void MotorsBackward()
{
    digitalWrite(motorL1, HIGH);
    digitalWrite(motorL2, LOW);
    digitalWrite(motorR1, HIGH);
    digitalWrite(motorR2, LOW);
}

void MotorsForward()
{
    digitalWrite(motorL1, LOW);
    digitalWrite(motorL2, HIGH);
    digitalWrite(motorR1, LOW);
    digitalWrite(motorR2, HIGH);
}

void MotorsStop()
{
    digitalWrite(motorL1, HIGH);
    digitalWrite(motorL2, HIGH);
    digitalWrite(motorR1, HIGH);
    digitalWrite(motorR2, HIGH);
}

void MotorsLeft()
{
    analogWrite(PwmLeft, 0); 
  analogWrite(PwmRight, 0);
    digitalWrite(motorR1, HIGH);
    digitalWrite(motorR2, HIGH);
    digitalWrite(motorL1, LOW);
    digitalWrite(motorL2, HIGH);
}

void MotorsRight()
{
      analogWrite(PwmLeft, 0); 
  analogWrite(PwmRight, 0);
    digitalWrite(motorR1, LOW);
    digitalWrite(motorR2, HIGH);
    digitalWrite(motorL1, HIGH);
    digitalWrite(motorL2, HIGH);
}

void Motors180()
{
    analogWrite(PwmLeft, 0); 
    analogWrite(PwmRight, 0);
    digitalWrite(motorL1, HIGH);
    digitalWrite(motorL2, LOW);
    digitalWrite(motorR1, LOW);
    digitalWrite(motorR2, HIGH);
}

void PIDController()
{
  if(digitalRead(SensorL) == HIGH){analogWrite(PwmRight, 250);analogWrite(PwmLeft, 0);}
  if(digitalRead(SensorR) == HIGH){analogWrite(PwmLeft, 250);analogWrite(PwmRight,0);}
  if((digitalRead(SensorL) == LOW) && (digitalRead(SensorR) == LOW)){analogWrite(PwmRight, 0);analogWrite(PwmLeft, 0);}
}

Now that's all, here's the video for Line Following Robot using Arduino which will give you better idea:

That's all for today. I hope you have enjoyed this Line Following Robot using Arduino and are gonna use it in your projects. feel free to ask in comments, if you got into any trouble. Thanks for reading. Take care !!! :)

Syed Zain Nasir

I am Syed Zain Nasir, the founder of <a href=https://www.TheEngineeringProjects.com/>The Engineering Projects</a> (TEP). I am a programmer since 2009 before that I just search things, make small projects and now I am sharing my knowledge through this platform.I also work as a freelancer and did many projects related to programming and electrical circuitry. <a href=https://plus.google.com/+SyedZainNasir/>My Google Profile+</a>

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