IEEE ECE LATEST SEMINAR

The World’s Largest Fusion Reactor


Since, 1932, researchers have been successful in combining hot fusion with nuclei. Till then the concept of cold fusion was used and did not produce any satisfactory results. The research in hot fusion is still continuing and they have been successful in providing danger-free, very good potential energy source without producing much wastes.
Some of the main advantages of a fusion power plant is that they will not produce any high radioactive waste which will live for a long period. They cannot be used as a deadly weapon and cannot be subjected to meltdown. Thus, it is clear that hot fusion reactor is a very good energy producer when compared to other low efficient conventional methods.
In order to produce such a reactor, an international research and experimenting project was made by the name International Thermonuclear Experimental Reactor (ITER). Researchers at ITER have decided to build the world’s biggest and most efficient “tokamak” nuclear reactor. Tokamak refers to the device that uses a magnetic field to restrict the plasma inside a vessel. Thus the fusion reaction process is experimented inside this vessel. The plasma that is restricted inside the vessel with the help of magnetic field is composed of deuterium and tritium, and two isotopes of hydrogen. The radio waves and micro waves, along with the particle beams rise the temperature inside the vessel to as high as 270 million degrees Fahrenheit. This is the minimum temperature that is required to support the fusion process.
The inside schematic of an ITER Tokahama nuclear reactor is shown below.




The basic working of a reactor is given below.
Firstly, the fuel in the form of two hydrogen isotopes, deuterium and tritium is injected into the tokamak. The vessel will be filled with plasma, a huge mix of changed particles, as soon as an electric current heats the deuterium and tritium gases and ionizes them.The plasma produces high temperature heat as soon as radio waves, microwaves and high-energy deuterium particle react with it. This high temperature causes further reaction between deuterium and tritium and forms products like helium atom and a neutron.
Great care has to be taken in avoiding the plasma from touching the wall of the fusion reactor. Since it will have high temperatures, they may cause holes on the walls and hence leakage. To avoid this from happening, the charged particle is restricted in a magnetic field made from 39 superconducting poloidal, toroidal and central solenoid magnets positioned inside and outside the doughnut shaped vessel. Since the walls may also be affected from high energy neutrons, a 2 feet thick steel blanket lining is also coated around the wall.
When a tritium and deuterium nuclei react together they give away helium and a neutron. If the same process is carried out inside a tokamak fusion reactor, it would produce enormous heat (energy) that is more than enough to generate electricity by rotating a turbine.
The whole experiment is to be carried out in a place called Cadarache, the south of France. The researchers claim that this reactor will be the largest tokamak in the world, since it is capable of producing 500 megawatts of power.
But, they have clearly stated that the whole process will just be an experiment and thus, the reactor will not be used to produce electricity. After an outline of the whole experiment is made and the budget estimated, the work will start by 2019. If it turns out to be successful, a 2,000 to 4,000 megawatt producing power plant will be built by 2040!!
According to Richard Pitts, a scientist who is working on the project, the whole process is claimed to be very safe. He says that there will be no hazards or radiation leaks like what happened in Chernobyl and Fukoshima.
In order to carry out experiments, the researchers will have to face a lot of technical problems. Some of them are
The breeding of tritium is extremely difficult since the material is scarcely found anywhere on Earth. At any time, only 50 pounds of tritium is produced and it has a high decay rate. This scarcity is because the material is not naturally produced. But, there will not be any problem in producing deuterium as it not radio-active and it can be distilled from water. They can use the tritium used in other power plants, but if high-end experiments are to be carried out, they will have to produce their own supply. Neutrons from the fusion reaction could be used to convert a little of lithium into tritium.The inside schematic of an ITER Tokahama nuclear reactor is shown below.
According to Richard Pitts, a scientist who is working on the project, the whole process is claimed to be very safe. He says that there will be no hazards or radiation leaks like what happened in Chernobyl and Fukoshima.
In order to carry out experiments, the researchers will have to face a lot of technical problems. Some of them are:
The breeding of tritium is extremely difficult since the material is scarcely found anywhere on Earth. At any particular time only 50 pounds of tritium is produced and it has a high decay rate. This scarcity is because the material is not naturally produced. But, there will not be any problem in producing deuterium as it not radio-active and it can be distilled from water. They can use the tritium used in other power plants, but if high-end experiments are to be carried out, they will have to produce their own supply. Neutrons from the fusion reaction could be used to convert a little of lithium into tritium.
The researchers must also know which material can be used to build tokamak walls, as it could be easily worn down from the reaction with the by-products from the fusion reaction.
There could also occur maintenance problems as the workers inside the vessel could be affected by residual radioactivity. Thus, they will have to design robots that are capable of carrying small tasks like replacing faulty parts and so on
.



Electrical and electronics latest seminars



EEE&ECE LATEST SEMINARS:


‘Cling-Film’ Solar Cells – A New Revolution for Renewable Energy




Scientists from the Universities of Sheffield and Cambridge have started a new research that promises to produce cost-effective and highly efficient cling film solar cells. The idea was first published in the journal “Advanced Energy Materials”. According to them, these solar cells can also be produced with much ease. This has clearly become a great advancement in the field of renewable solar energy.
To carry out the tests, the ISI Neutron Source and Diamond Light Source at STFC Rutherford Appleton Laboratory in Oxfordshire were used.
Until now, two types of solar cell materials are being used – plastic and silicon. When it comes to manufacturing of the material, plastic is known to be much much cheaper. Due to the simple manufacturing process, they can also be produced in huge quantities. When molecules having complex mixtures are spread on to a surface, the molecules move away from one another and start to accumulate at the top and bottom of the layer. Thus, a highly efficient solar cell is produced. This same principle was used by researchers to prove that by using much better and cost less manufacturing methods, where flexible layers of material are deposited over large areas like cling-film, highly efficient solar cell structures can be produced.
These solar cells are known to be useful for both home use as well as industrial use and since it is very cheap, it can be manufactured on a high-scale. Instead of using high-end fabrication methods to manufacture a certain semi-conductor nanostructure, high number of printing could be used to produce nano-scale films of solar cells that are much thinner than the width of a human hair. Such films can be used to produce cost-effective, light-weight solar cell panels.
According to Dr. Robert Dalgliesh, one of the researchers of the project, the work makes us understand the potential of the joint use of neutron and X-ray scattering sources such as ISIS and Diamond in solving modern challenges for society. Using such sources help in making a stronger internal structure for the solar cell. By studying the layers in the solar cell that is responsible in converting sunlight into electricity, the different processing steps that change the overall efficiency and affect the overall polymer solar cell performance is also known.
Since most of the energy consumed today is through non-renewable sources, the demand for something that generates energy through a renewable source like the Sun is needed for the coming years. Since no highly efficient system that is capable of converting sunlight into electricity has been found until now, the cling-film solar cell will clearly pave way for the new age of renewable energy
.

ECE LATEST SEMINAR TOPICS

ELECTRONICS LATEST SEMINARS:  PIR Sensor Based Security System


The circuit of an inexpensive and highly secure electronic security system is explained below. This electronic security system can be used in banks and other high security areas.
A normal electronic security system will have a transmitter and a receiver. The transmitter sends out an IR laser and this will be received by the receiver. When an intruder walks past the device, the IR beam is cut and thus the alarm is activated. But, this system has some major disadvantages like limited range and poor line of sight. These disadvantages are eliminated through the PIR sensor circuit explained below.

Working

Instead of infrared or laser transmitters and receivers, PIR (Passive Infrared Radial) sensors are used in this circuit. The sensor is basically a pyroelectric device. When the device is exposed to infrared radiation, it generates an electric charge. The device is made of crystalline material. According to the change in the amount of infrared striking the element, there will be a change in the voltages generated, which is measured by an on-board amplifier.
The infrared light explained here refers to the light radiating from all objects in its field of view. The reason for not having a transmitter and receiver is that the device does not emit one, but only accepts the energy emitted from objects above absolute zero in the form of radiations. Thus the temperature will be different for a human working past a sensor, and that of a wall right in front of it. Thus the word “passive” is used in PIR to explain that it does not emit a radiation and receive it, but instead accepts the incoming infrared radiation passively.

The block diagram of the PIR based security system is given below.





The device contains a special filter called a Fresnel lens, which focuses the infrared signals onto the element. As the ambient infrared signals change rapidly, the on-board amplifier trips the output to indicate motion. We can say that the PIR sensor is a human body sensor because it is only activated when a human or animal walks past the sensor. The PIR sensor is the heart of the project. We can design the project in such a manner that as soon as the burglar or intruder walks past the sensor, the alarms would turn on and the whole lighting system could turn on.

Circuit Diagram




  • PIR Sensor
D204B PIR sensor is used in this project. The PIR sensor is the heart of the project.
  • Two Stage Amplifiers
Two stage OP-amp: LM 324 is used as two stage amplifier. The signal from the PIR sensor is very low so this signal is amplified by using LM324.LM324 is a quad OP-amp. First two op-amps act as amplifiers.
  • Comparator
The comparator compares the signal from the amplifier and a reference voltage.3rd and 4th OP-amp of LM 324 act as comparator.
  • Transistor Switch
Whenever the output of comparator make HIGH Q1 transistor gets ON and relay will be energized causing the alarm and lamp to turn ON.
  • Power Supply
Power supply converts 230 Volt AC into 12 Volt DC and 5 Volt DC. IC 7812 is used as the 12 Volt voltage regulator and a 5v zener diode act as the 5 Volt voltage regulator









ECE SEMINAR TOPICS

ECE SEMINAR TOPICS: smart dust

INTRODUCTION
The current ultramodern technologies are focusing on automation
and miniaturization. The decreasing computing device size, increased
connectivity and enhanced interaction with the physical world have
characterized computing’s history. Recently, the popularity of small
computing devices, such as hand held computers and cell phones; rapidly
flourishing internet group and the diminishing size and cost of sensors and
especially transistors have accelerated these strengths. The emergence of
small computing elements, with sporadic connectivity and increased
interaction with the environment, provides enriched opportunities to
reshape interactions between people and computers and spur ubiquitous
computing researches.
Smart dust is tiny electronic devices designed to capture mountains
of information about their surroundings while literally floating on air.
Nowadays, sensors, computers and communicators are shrinking down to
ridiculously small sizes. If all of these are packed into a single tiny device,
it can open up new dimensions in the field of communications.
The idea behind ‘smart dust’ is to pack sophisticated sensors, tiny
computers and wireless communicators in to a cubic-millimeter mote to
form the basis of integrated, massively distributed sensor networks. They
will be light enough to remain suspended in air for hours. As the motes
drift on wind, they can monitor the environment for light, sound,
temperature, chemical composition and a wide range of other information,
and beam that data back to the base station, miles away.