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Monday, March 31, 2008

DSP based control of slipring induction motor

DSP based control of slipring induction motor

This project deal with the control the speed of slip ring induction motor using Digital signal processing. The main intension is to design a system which gives accurate speed control with maximum efficiency and without any energy loss. In the existing methods of speed control it is possible to control either the stator or rotor section, but this system can control both the stator and rotor.
This document presents a solution to control an AC induction motor using the
TMS320LF2407A. This new family of DSP controllers enables cost-effective design of
Intelligent controllers for AC motors which can yield enhanced operation, and increased efficiency. The algorithm maintains efficiency in a wide range of speeds and takes into consideration torque changes with transient phases by processing a dynamic model of the motor.

Pulze Width Modulation is the most commonly used method for the speed control of any motor. PWM inverters where designed using either BJT or MOSFET. The insulated gate bipolar transistor (IGBT), which was introduced in the early 1980s, has become a successful
device because of its superior characteristics. The IGBT is a three-terminal power semiconductor switch used to control electrical energy. Prior to the advent of the IGBT, power bipolar junction transistors (BJTs) and power metal oxide field effect transistors (MOSFETs) were widely used in low to medium power and high-frequency applications,
Where the speed of gate turn-off thyristors was not adequate. So we are using IGBT based PWM inverter for accurate speed control.

The choice of DSP kit is to make the digital control of motor possible. Analog speed control methods have a big disadvantage of energy loss which is greatly minimized using digital control.

Saturday, March 29, 2008

All about circuits forum

All about circuits forum

Yesterday i visited a forum website which is purely dedicated to discusses topics on Embedded system and microcontroller, Electronics circuit chats, Various proect collections on engineering projects, Computer networks and communications. I am amazing to see such website which deals with all sort of topics on latest science, engineering and technology. here is webshot of this site

In this site you can upload your projects or read or discuss projects of all kind.
Some of the other forums in this series are
Forum on Microcontroller, FPGA and CPLD, Embedded systems/

Friday, March 28, 2008

Matlab basics and applications projects review2

Matlab basics and applications projects review2

I would like to discuss Matlab which is called as Matrix lab. Matlab is widely used in engineering and Technology fields. I would like to share some of the websites offering matlab projects.

1.Matlab Projects:

MATLAB is a data-manipulation software package that allows data to be analyzed and visualized using existing functions and user-designed programs. MATLAB is a numerical computing environment and programming language. MATLAB allows easy matrix manipulation, plotting of functions and data, implementation of algorithms, creation of user interfaces, and interfacing with programs in other languages. Although it specializes in numerical computing, an optional toolbox interfaces with the Maple symbolic engine, allowing it to be part of a full computer algebra system.

some of the matlab applications listed are

Orthogonal frequency division multiplexing
Genetic algorithm data mining
Speech recognition using VQ method
Channel Estimation and Detection in DS-CDMA
Analysis of iterative channel estimation and multi-user detection in multi path DS-CDMA channels
Estimation of mimo Channels
Training signal design for estimation of correlated mimo channels with colored interference.
Time-domain signal detection
Time-domain signal detection based on second-order statistics for mimo-OFDM systems
Multi user detection for DS-CDMA
On minimum-BER linear multi user detection for DS-CDMA channels
Space–time block coding
Quasi-orthogonal time-reversal space–time block coding for frequency-selective fading channels
Space–time block codes for mimo channels
Pre coded orthogonal space–time block codes over correlated ricean mimo channels
Blind channel estimation
Blind channel estimation for mimo OFDM systems via non redundant linear pre coding
Multi node communications
Multi node cooperative communications in wireless networks

2. This site in additionally provide embedded projects also

Applications are
Broken Bag Detector
Incubator System
Unmanned Gate Control System
Plc Based Green House

3.Wireless Projects
Radio-based systems that allow transmission of information without a physical connection. Using the radio-frequency spectrum for transmitting and receiving voice, data and video signals for communications. Telecommunications systems (e.g., radio transmitters and receivers, remote controls, computer networks, network terminals, etc.) which use some form of energy (e.g.,radio frequency (RF), infrared light, laser light, visible light, acoustic energy, etc.) to transfer information without the use of wires.Information is transferred in this manner over both short and long distances.
Some of the applications are listed here

Automatic Toll Tax
It’s a wireless automatic toll paying system which transmits a particular code as soon as it reaches near the toll station , on receiving the code receiver processor checks the received code and compare with the stored code if code matches it open the gate else does not allow the vehicle to pass .

Electronic Road Pricing (ERP)
An Automatic Identification And Authentication System Which Reads Vehicles Account Validity and deduct the value from its EEPROM card And allow users to pass through the road if any one try to escape camera will automatically switch on.

Product Authentication System
Wireless Enrgy Meter
Explosive Detection System

Thursday, March 27, 2008

Engineering Projects websites review1

Engineering Projects websites review1

Today i visited some websites which offer engineering projects and training for the student to do projects in areas describing below

1. Vi Microsystems: This sites offer engineering projects for final and pre final year students and also manufacturer of engineering products on embedded systems, VLSI technology, MueC/OS II RTOS support for PIC microcontrollers, ARM7, ARM9 processors, PLC and instrumentations., embedded system kits and so on.

This site also offer training on embedded systems and VLSI.

Vi microsystemes organises a international seminar on 10-11th April 2008 on Embedded platform and Design tools
Some their products are

USB to Serial Peripheral Converter
Releasing new design board, which converts USB signals to RS232,I2C,SPI,CAN compatible levels.
Advanced FPGA Module
New Universal FPGA Module supports Xilinx Virtex 4 devices with USB & Ethernet connectivity
VI LAN TRAINER
Network Concept Level Teaching & Training module.

Wednesday, March 26, 2008

Microcontroller project pages review

Review of project sites:
I am very happy that this site is gaining more popularity of its content. Thank for the visitors and engineering project enthusiastic people
Microcontroller project pages review Here i would like to share some of the websites which deals with micro controller projects, articles related to microcontroller, embedded system related projects for engineering students studying in final year, some of the top sites are here
1. Programming PIC MCUs in BASIC :
This sites deals with the basics of PIC microcontroller, programming basics, hardware and so on. This will give some deep insight before start to do projects in this controller in electrical and electronics applications.
for project pages click here

2. Microcontroller, FPGA, Embedded projects:
This sites offer projects on Microcontroller, FPGA and Embedded related projects and it has forum related to these projects where u can discuss on various topics
Some of the sample projects are
Short Range Personal Radar, FPGA projects

3. Technical blog
This blog discusses various technical articles which are new concepts

Tuesday, March 25, 2008

cascade multilevel inverter

cascade multilevel inverter
Abstract
A method is presented showing that a cascade multilevel inverter can be implemented using only a single DC power source and capacitors. A standard cascade multilevel inverter requires n DC sources for 2n + 1 levels. Without requiring transformers, the scheme proposed here allows the use of a single DC power source (e.g., a battery or a fuel cell stack) with the remaining n-1 DC sources being capacitors. It is shown that one can simultaneously maintain the DC voltage level of the capacitors and choose a fundamental frequency-switching pattern to produce a nearly sinusoidal output.
Basics behind this project:
Power-electronic inverters are becoming popular for various industrial drives applications. In recent years also high-power and medium-voltage drive applications have been installed. To overcome the limited semiconductor voltage and current ratings, some kind of series and/or parallel connection will be necessary. Due to their ability to synthesize waveforms with a better harmonic spectrum and attain higher voltages, multi-level inverters are receiving increasing attention in the past few years. The multilevel inverter was introduced as a solution to increase the converter operating voltage above the voltage limits of classical semiconductors. The multilevel voltage source inverter is recently applied in many industrial applications such as ac power supplies, static VAR compensators, drive systems, etc. One of the significant advantages of multilevel configuration is the harmonic reduction in the output waveform without increasing switching frequency or decreasing the inverter power output. The output voltage waveform of a multilevel inverter is composed of the number of levels of voltages, typically obtained from capacitor voltage sources. The so-called multilevel starts from three levels. As the number of levels reach infinity, the output THD (Total Harmonic Distortion) approaches zero. The number of the achievable voltage levels, however, is limited by voltage unbalance problems, voltage clamping requirement, circuit layout, and packaging constraints. Multilevel inverters synthesizing a large number of levels have a lot of merits such as improved output waveform, a smaller filter size, a lower EMI (Electro Magnetic Interference), and other advantages. The principle advantage of using multilevel inverters is the low harmonic distortion obtained due to the multiple voltage levels at the output and reduced stresses on the switching devices used. Improvements in fast switching power devices have led to an increased interest in voltage source inverters (VSI) with pulse width modulation control (PWM). It is generally accepted that the performance of an inverter, with any switching strategies, can be related to the harmonic contents of its output voltage. Power electronics researchers have always studied many novel control techniques to reduce harmonics in such waveforms. Up-to-date, there are many techniques, which are applied to multilevel inverter topologies. Pulse Width Modulation (PWM) is widely employed to control the output of static power inverters. The reason for using PWM is that they provide voltage and/or current wave shaping customized to the specific needs of the application under consideration. It is lastly performance and cost criteria, which determines the choice of a PWM method in a specific application. PWM inverters can control their output voltage and frequency simultaneously. And also they can reduce the harmonic components in load currents. These features have made them power candidate in many industrial applications such as variable speed drives, uninterruptible power supplies, and other power conversion systems. However, the reduction of harmonic components in output currents is still the focus of major interest to alleviate the influences of electromagnetic interferences or noise and vibrations.
In general, neutral point clamped PWM three-phase inverter which uses four switching elements in each arm has the five- level voltage waveforms that results in considerable suppression of the harmonic currents comparing with the conventional full-bridge type three-level PWM inverters. However, this is not the case of single-phase PWM inverter. In these days, the popular single-phase inverters adopt the full-bridge type using approximate sinusoidal modulation technique as the power circuits. The output voltage of them has three values: zero, positive and negative supply dc voltage levels. Therefore, the harmonic components of their output voltage are determined by the carrier frequency and switching functions. Moreover, the harmonic reduction of them is limited to a certain degree. Under these technical backgrounds, a single-phase three-level PWM (Pulse Width Modulation) is presented in the project.

Monday, March 24, 2008

Review of Engineering project websites

Review of Engineering project websites

I have visited some of websites which are purely offering electronics, microcontroller, VLSI technology, microprocessor, FPGA, CPLD related engineering projects in india and abroad. I would like to list these websites here. Credits and thanks to those websites.

1.Circuit Project Electronic offer various electronic circuits like DC to DC converter, DC to AC converter, switching regulators, power amplifiers, Integrationg ics, battery chargers and so on.

2. Science projects : This site offers microprocessor and embedded systems, AVR and ARM microcontroller, Biomedical electronics, DSP related projects.

3. Electronics circuits : This sites offer Power supply,DC converter,Inverter, TV,Monitor,Battery Charger, Digital and circuit related mini circuit projects.

Sunday, March 23, 2008

Nanowire LED light

Nanowire light, LED light
Light-emitting diodes that give a warm glow to your home or office will be available within a few years, say Swedish researchers working with nanowires.
Professor Lars Samuelson and team at Lund University are aiming to produce devices that do not cast as harsh a light as existing LEDs, and that are more efficient and longer lasting.
"We can really make the three colours - red, green and blue - with this technology and get warm LEDs," says Samuelson, who presented his research at the recent International Conference On Nanoscience and Nanotechnology in Melbourne.
Conventional LEDs are made of multiple crystalline semiconductor layers that emit light when a current passes through them, converting 30% of the electricity they receive into light.
But these LEDs are often used in small applications like torches, bicycle lights and reading lamps, rather than on a larger scale.
This is because defects in the crystal structure of the semiconductors limit their efficiency when scaled up.
"Even the commercial LEDs you buy today for your flashlight, for instance, have 10 million defects per square centimetre," says Samuelson, of the university's Nanometer Structure Consortium.
Samuelson's team have found a way to produce what they say are defect-free LEDs.
Forests of nanowires
The researchers have been making LEDs out of forests of long, thin nanowires grown from gallium arsenide and indium gallium phosphate.
Millions of these nanowires, each 2 micrometres tall and less than 200 nanometres in diameter, produce "highly perfect structures", says Samuelson.
He says they will last longer and be useful in large-scale home and office lighting, with an efficiency of around 50%, more efficient than existing incandescent or fluorescent lighting.
By comparison, an incandescent light bulb is only 4% efficient, a compact fluorescent 25%.
The nanowire LEDs are brighter than existing LEDs and can emit light more easily to their surrounds, Samuelson says.
They can be tuned to give warm colours, by adjusting the concentration of different elements in the crystalline structure.
New crop of LEDs
Samuelson says the research has been funded by Swedish and European research programs and he is involved in a start-up company to commercialise large-scale LED lighting within the next three years.
Other researchers are working towards warmer LEDs for use in home lighting using methods other than nanowires.
But nanowire LEDs are expected to be the most efficient, says Australian nano-engineering expert Professor Chennupati Jagadish
courtesy: source

Friday, March 21, 2008

Amazing future lightbulb

Amazing future lightbulb
Can you imazine a future light will look like, here its size is unimaginably very small, and its brightness which can not be describe by words, see it here

Luxim's plasma lightbulb
Silicon Valley's Luxim has developed a lightbulb the size of a Tic Tac that gives off as much light as a streetlight.

size of the bulb

Wednesday, March 19, 2008

SMS BASED INDUSTRIAL AUTOMATION USING PERSONAL COMPUTER

SMS BASED INDUSTRIAL AUTOMATION USING PERSONAL COMPUTER
ABSTRACT
The short message system (SMS) of a standard mobile phone can be used for much more than just exchanging cryptic message. This application finds a humble mobile working in a remote site monitoring and controlling external equipments. The SMS service provides by the service providers are comparatively low cost. Hence the system is highly efficient and low cost. It can be implemented for a variety of industrial applications.

In this SMS techniques together with the micro controller technology are used in a wide variety of applications in industry, including computer peripherals, business machines, motion control, and robotics, which are, included in process control and machine tool applications. The automation system is designed by keeping in mind that it should be user friendly and it should be possible to operate it from anywhere in the world. This system is designed in such a way to reduce the wiring complexity and manpower. Thus the system provides an excellent hold as per industrial motion control systems.

Mobile phones have become a widespread means of communication. It becomes a part of everyday life with ever more people enjoying the service and extra freedom they provide. It works on the basis of Global System for Mobile Communication (GSM). A subscriber from any systems can access telecommunication services by using a Subscriber Identify Module (SIM) card in a handset suitable for the network on the visited system The Short Message Service allows text messages to be sent and received to and from mobile telephones. The text can comprise words or numbers or an alphanumeric combination. Because Simple person - to - person messaging is such an important component of total SMS traffic volumes, anything that simplifies message generation as well as extended utility of the SMS being sent is an important enabler of Short Message Service. Such extended utility of SMS fulfills certain important requirements. Keeping this in mind the research work “ SMS BASED INDUSTRIAL AUTOMATION USING PERSONAL COMPUTER " is developed. This system is developed to control the functions of a device from a remote area through the SMS of a mobile phone using personal computer and Micro controller.

The short message service (SMS) of a standard mobile phone can be used for much more than just exchanging cryptic message. This application finds a humble mobile working in a remote site monitoring and controlling external equipment. This system accommodates the SMS techniques together with the micro controller technology that are used in a wide variety of applications in industry via computer peripherals, business machines and robotics that are related to process control and machine tool applications. This Automation system is designed in such a way that it has to be user friendly and it must be possible to operate it from anywhere is the world.
"

EMBEDDED SYSTEMS - AN OVERVIEW

Breathtaking developments in microelectronics, processors speed and memory elements accompanied with dropping prices have resulted in powerful embedded systems with a number of applications.The intelligence of smart devices resides in embedded systems. An embedded system in general incorporates hardware, operating system, low­ level software binding such as, peripheral devices and communication software to enable the device to perform pre-defined functions.

A plethora of processors are variable to cater to different applications. 8 bit, 16 bit and 32 bit processors are available with different processing powers and memory addressing capabilities. Advanced Digital Signal processors (DSPs) cater to AV coding and image processing. Embedded systems are built around processor boards. These processors boards incorporate necessary RAM, ROM and peripheral such as USB port and serial port.

DSP based embedded systems are available for diversifications, with circuitry being specific to the application on hand. Sensors, transducers, relay I/O devices and special circuitry interfaces to the processor board are the various elements in action.

We stand to immensely benefit from modern embedded gadgets armed with powerful processing, adaptable memory, and sophisticated software managing complex information and communication protocols. In the future smart gadgets would connect and initiative action on our behalf.
DESCRIPTION
The short messages such as stepper on, stepper off etc, (at a time only one) are delivered to the Nokia mobile phone, which is kept at the receiving end from the transmitting section using a mobile phone. In the receiver section this mobile is connected to the personal computer through the com port. The master micro controller is connected to the parallel port through the octal buffer and line deriver. The port 0 of the micro controller is connected to the stepper motor driver through the actual buffer and line driver. The stepper motor whose motion to be controlled, is connected to a driver. Another port (i.e.) port 2 of the micro controller is connected to the LED indicators via the octal buffer and line driver. The necessary power required to all the parts are supplied by the suitable power supplies.

Messages such as stepper on, stepper off etc to control the motion of the stepper motor are received by the mobile phone kept in the receiving side and are read by the personal computer for which the software for Nokia PC connectivity is enabled. To control the various motion control operations of the stepper motor from remote place, the Front End Design as well as application is developed using Visual Basic 6.0. The application always monitors the inbox of the mobile and the received SMS is accepted only if the transmitted mobile phone number is available in the database of it. If not, simply it shows the message.
"Received message from unauthorized phone" and message will be deleted. It shows the design and ensures that the system is highly protected and cannot be operated by any unauthorized persons.

When any message with one of the above commands (stepper on, stepper off, etc) received from the authorized mobile phone number the application sends corresponding information to the micro controller through the interfacing device (octal buffer and line driver). The micro controller reads the data and delivers the corresponding information to control the motion of the stepper motor. At the same time the corresponding LED will indicate the status of the motion what is going on. Which indicate the various commands received by the mobile and during the sequence of operations performed.

The maximum speed or minimum is reached when the corresponding command is continuously send to the receiving mobile. During that time, the message “can’t increase the above current speed” “can’t decrease the above current speed” will get displayed in the screen. The system is capable of continuously functioning round the clock.

RESULTS AND DISCUSSIONS

The developed system " SMS BASED INDUSTRIAL AUTOMATION USING PERSONAL COMPUTER " is used to control the functions of a device from a remote area through the SMS of a mobile phone using personal computer and micro controller.

From the transmitting section using a mobile phone, short messages are delivered to the Nokia Mobile Phone. In the receiver section this mobile is connected to the Personal Computer. This in turn is connected to micro controller, which controls the motion of the stepper motor. This system is designed in such a way that it has to be user friendly and it must be possible to operate it from anywhere in the world.

It compensates all the drawbacks of the landline telephone due to the inclusion of enhanced feedback and monitority facility. It acts as a better remote mobile operation. This project can be modified according to the industry requirements. Only an attempt has been made here to control the motions of the stepper motor using this developed system. This could be further more researched, wherein the same application can be utilized to control any other hazardous devices or similar devices in place of the stepper motor.

List of engineering project sites

I searched for sites which offer engineering projects for final & free final year students in the field of embedded system, robotics, VLSI and other technology oriented. here are some lists to follow,
1. Microcontroller projects (8051 microcontroller)
All final Year Engineering Students Are you looking for Projects at an affordable price With training And with guidance uptill Viva . Click Here for More details on projects .

2. Cmputer and electronic projects

Here, the projects category varies from zigbee sensors, bluetooth based remote control for servomotors, security for remote control and so on.
3. Industrial projects

This include major industrial level projects

Tuesday, March 11, 2008

CONVERSION OF ROTARY HEARTH FURNACE RELAY LOGIC TO PLC

CONVERSION OF ROTARY HEARTH FURNACE RELAY LOGIC TO PLC
In BHEL like companies, seamless tubes are extensively used in power stations, marine boilers, refineries, and for oil & gas exploration applications besides industries such as petrochemicals, fertilizers, textiles, automobiles, paper, sugar, etc.

Programmable logic controllers (PLCs) are nowadays becoming more popular in industrial process control applications because of the most of their advantages. The rotary hearth furnace (RHF) is one such unit used in industrial process, which requires more advanced control for its operation. In this project attempt has been made to automize the control function of Rotary Hearth Furnace in BHEL using PLC. This project deals with the design of the ladder logic from the relay logic for the Rotary Hearth Furnace unit through PLC.

The conversion of Relay logic to PLC has imparted good flexibility, fast implementation of changes in control program, easier trouble shooting, high speed operations and more reliability.

Friday, March 7, 2008

REMOTE CONTROL OF OVERHEAD CRANE

REMOTE CONTROL OF OVERHEAD CRANE

This project entitled “REMOTE CONTROL OF OVERHEAD CRANE” has been developed for remote operation of overhead crane using Radio Frequency, and this project over comes the present day draw backs of OH crane.

In case of overhead crane, the entire crane structure will be enclosed inside a large room. In industries such cranes are used for carrying tons and tons of loads. The loads to the crane are normally very far from the operator’s view. Thus this project helps the operator to be near the load, by providing remote operation

For such a remote operation microcontroller ATMEL 89S52 has been preferred due to its special features. In this system, the microprocessor continuously scans for any key press from the matrix key pad. As soon as the microcontroller recognizes the key press it generates a code corresponding to the key which has been pressed.

Then the encoded code is modulated and transmitted through the transmitter section. At the receiver section the demodulated code is multiplexed to the corresponding motor which controls the direction and movement of the OH crane.

Wednesday, March 5, 2008

Embedded projects review

Embedded projects review
I would like to review and site details where the students doing final year projects on Embedded controller based projects.
1. This site offer live Embedded projects for for EEE, ECE, CSE, Instrumentation, biotechnology, Biomedical & Mechanical engineering disciplines.
This site also concentrate on Micro controller & Robotic project based on embedded controller

Areas of final year projects

For engineering students, it is mandatory to do a project work at final year. I would like to list the areas where one can choose his project works ( Electrical and Electronics, Electronics and Communications, VLSI branches i.e only for circuit branches
1. VLSI based projects
Hardware platform : FPGA, CPLD ..
Software platform : Xilinx, Altera ..
2. DSP based projects
Hardware kits : DSP 2407 series ..
3. Microcontroller based projects
4. Microprocessor based projects
5. ARM processor based projects
6. GPS or GPRS, GSM based projects
7. Drives related projects
8. Solar power / Energy, Wind like renewable sources related projects
9. IEEE paper based projects
IEEE journals may be taken reference for doing and implementing the projects
10. Wireless communication related projects e.g. zigbee network
11. SMS based control projects
these are all the some areas where u can choose projects

Tuesday, March 4, 2008

IMPLEMENTATION OF STEP UP BOOST CONVERTER USING VIRTUAL INSTRUMENTATION

IMPLEMENTATION OF STEP UP BOOST CONVERTER USING VIRTUAL INSTRUMENTATION
This project describes the implementation of boost type DC/DC converter in continuous conduction mode and discontinuous conduction mode of operation. This converter circuit, step up the input voltage without a transformer. The main application of boost converter is regenerative braking of dc motors and regulated dc power supplies. Triggering pulses for the converter are generated by using IC 555 timer and the voltage across the load can be stepped up by varying the duty cycle. This complete circuit is simulated by using National Instruments Educational Laboratory Virtual Instrumentation Suite and LabVIEW software. The NI ELVIS suite consists of a PCI multifunctional Data Acquisition system, a workstation a prototype board and provides a suite of virtual laboratory instruments. The LabVIEW software is employed for continuous monitoring of the output voltage. The NI ELVIS measurement provides a better solution when compared with traditional instruments.

Monday, March 3, 2008

FUZZY LOGIC CONTROL OF A WIND DRIVEN DC GENERATOR

FUZZY LOGIC CONTROL OF A WIND DRIVEN DC GENERATOR
The purpose of control is to influence the behavior of a system by changing an input (or inputs) to that system according to a rule or set of rules that model how the system operates. The system being controlled may be mechanical electrical, chemical or any combination of these. A battery charging system employing a Wind Turbine Generator (WTG), with a step-up DC chopper (using a MOSFET) interposed between them, requires a control strategy for the optimum charging of the battery. The charging current to the battery and the output of the generator varies with the wind speed and the state of charge of the battery. Therefore, to maintain maximum charging current to the battery, controller is needed which can vary the duty cycle of the step-up chopper, based on the turbine output (i.e., the torque TL, which depends on the wind speed) and the state of charge of the battery (i.e., the battery voltage, Vb).

Fuzzy logic can make control engineering easier for many types of tasks and also add control where it was previously impractical, as applications such as fuzzy-controlled washing machines. Keeping in mind the inherent advantages of using fuzzy logic, a Fuzzy Logic Controller has been designed to control the duty cycle of the step-up chopper for the reasons mentioned above.
The control rules for the designing were framed based on a simulation study of a wind turbine generator set-up feeding a battery and a load. The scheme with the FLC was simulated in MATLAB using simulink and the built in block sets like the Power System Block sets. The duty cycle was found to vary as expected and the charging current to the battery was found to be optimum in all cases.

Power-line Communication and Data Transmission

power-line communication
This project is about power-line communication over the low-voltage grid. The main advantage with power-line communication is the use of an existing infrastructure. Wires exist to every household connected to the power-line network.
Project starts with a general introduction to power-line communication. Then an existing application, communicating on a low-voltage grid, is investigated in order to obtain some knowledge of how the power line acts as a communication channel.
The power-line communication channel can, in general, be modeled as having a time varying frequency-dependent signal-to-noise ratio over the communication bandwidth. Robust, low-complexity, modulation methods are investigated which simplifies the implementation of transmitter and receiver.
There are two obvious ways to decrease the strain on the power line infrastructure. One is to build more grids and other is to make the grids more efficient. The latter is a better option because building more inefficient grids will not decrease the problems that are faced with.
The key solution to this problem is Power Line Data Transmission (PLDT). PLDT can ease the congestion and load on the power lines, and also, give the electric companies the chance to offer new services such as broadband internet access and Power on Demand.
A communication strategy is described that eventually could be used for information transfer over the power-line communication channel. In order to achieve effective communication, the transmitter with better impedance matching and frequency modulation techniques are implemented. Similarly receiver is designed with better tuning and filtering to reproduce the exact message.

Prepaid Energy Meter

prepaid energy meter
The aim of this project is to design a prepaid energy meter to monitor the consumption of electricity in domestic needs. The standard business model of electricity retailing involves the electricity company billing the customer for the amount of energy used in the previous month or quarter. In some countries, if the retailer believes that the customer may not pay the bill for what ever reason a prepayment meter may be installed. This requires the customer to make advance payment before using the electricity. If the available credit is exhausted then the supply of electricity is automatically cut off by a relay.
Here analog energy meter is replaced by a digital energy meter. The digital energy meter used here is a high accuracy, low cost, single phase power meter based on the ADE7757.The meter is designed for use in single phase 2 wire distribution system. A relay is connected in between power lines and the load. The relay is controlled by the primary controller.
Microcontroller 89C51 acts as the primary controller. The primary controller collects information from digital energy meter as well as from the smart card. Smart gives information about the limitation of units. The digital energy meter reading is compared with the smart card information by the primary controller and hence suitably primary controller controls the relay.

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