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PROJECT REPORT

AIM
SPEED BRAKER ELECTRICITY GENERATION

INTRODUCTION Before starting I have one question to you all who is really very happy with the current situation of the electricity in India? I suppose no one. So this is my step to improve the situation of electricity with an innovative and useful concept ie Generating Electricity from a Speed breaker First of all what is electricity means to us? Electricity is the form of energy. It is the flow of electrical Power. Electricity is a basic part of nature and it is one of our most widely used forms of energy. We get electricity, which is a secondary energy source, from the conversion of other sources of energy, like coal, natural gas, oil, nuclear power and other natural sources, which are called primary sources. Many cities and towns were built alongside water falls that turned water wheels to perform work. Before electricity generation began slightly over 100 years ago, houses were lit with kerosene lamps, food was cooled in iceboxes, and rooms were warmed by wood-burning or coal-burning stoves. Direct current (DC) electricity had been used in arc lights for outdoor lighting. In the late-1800s, Nikola Tesla pioneered the generation, transmission, and use of alternating current (AC) electricity, which can be transmitted over much greater distances than direct current. Tesla's inventions used electricity to bring indoor lighting to our homes and to power industrial machines. How is electricity generated?

Electricity generation was first developed in the 1800's using Faradays dynamo generator. Almost 200 years later we are still using the same basic principles to generate electricity, only on a much larger scale. The rotor(rotating shaft) is directly connected to the prime mover and rotates as the prime mover turns. The rotor contains a magnet that, when turned, produces a moving or rotating magnetic field. The rotor is surrounded by a stationary casing called the stator, which contains the wound copper coils or windings. When the moving magnetic field passes by these windings, electricity is produced in them. By controlling the speed at which the rotor is turned, a steady flow of electricity is produced in the windings. These windings are connected to the electricity network via transmission lines. Now I m throwing some light on the very new and innovative concept ie GENERATING ELECTRICITY FROM A SPEED BREAKER. Producing electricity from a speed breaker is a new concept that is under going research. The number of vehicles on road is increasing rapidly and if we convert some of the kinetic energy of these vehicle into the rotational motion of roller then we can produce considerable amount of electricity, this is the main concept of this project. In this project, a roller is fitted in between a speed breaker and some kind of a grip is provided on the speed breaker so that when a vehicle passes over speed breaker it rotates the roller.

This movement of roller is used to rotate the shaft of D.C. generator by the help of chain drive which is there to provide 1:5 speed ratios. As the shaft of D.C. generator rotates, it produces electricity. This electricity is stored in a battery. Then the output of the battery is used to lighten the street lamps on the road. Now during daytime we don’t need electricity for lightening the street lamps so we are using a control switch which is manually operated .The control switch is connected by wire to the output of the battery. The control switch has ON/OFF mechanism which allows the current to flow when needed. One question that u all are thinking is why I have apply this on the speed breaker and not on the rough road or plane road where the kinetic energy of the vehicle is more then what I m getting on the speed breaker I m giving u one example, just think over it. A car or any heavy vehicle is coming with a speed of 100 mph on the road and passing over this roller which is fitted at the level of the road then this roller is gaining the speed nearly somewhere 90 mph (due to losses). So now suppose a cycle is coming with a speed of 20 mph and is going to pass this roller (which is moving at a speed of 90 mph) due to this difference in the speed there will be a collision that is the main reason for using this concept on the speed breaker

Side View

Top View

CONCLUSION AND FUTURE SCOPE In this world where there is shortage of electrical power supply, this project will be helpful to solve some of the problems. This project has some advantages which are:- The project is economical and easy to install. - This project is none polluting. - Maintenance cost is low. - Installation cost is low. - Will solve some of the electricity problems of the world. - The electricity produced by this system can be used to drive an electric motor or for any other purpose. This project can be implemented on road and can be used to lighten the street lamps

A control system for an AC excited synchronous machine for use in an electricity generator/motor system. The AC excited synchronous machine can be driven not only in a variable-speed operation based on 2-axis current control but also in a constant exciting frequency operation based on only direct-axis current component control. A phase signal is switched to drive stably the AC excited synchronoius machine in a self-excited operation or in a rotary phase modifying operation. Further, when it is desired to start pumping-up water, a synchronizing power is provided to keep constant the rotational speed of the machine at the time of establishing a desired water pressure.

Because of the switching arrangement of the phase signal, the AC excited synchronous machine can be operated as an ordinary synchronous machine exhibiting ordinary synchronous characteristics, that is, self-excited operation characteristics, rotary phase modifying operation characteristics and pumping-up start characteristics. Even when the synchronous machine is cutoff from an AC power system and the voltage of the synchronous machine is abruptly changed, the stable self-excited operation of the machine can be realized.

Dynamos In simplest terms, a dynamo is essentially an electric motor run in reverse. The electric motor uses magnets spinning in a metal coil to spin an axle. Conversely, spinning the axle causes the magnets to rotate in the coil and generates an electric current moving away from the motor. A cool experiment to try is to buy a small motor from radio shack and put it to your tongue. Spin it and you will feel a slight tingle coming from the connectors. This is known as the Faraday Effect. Look up this effect to gain a fuller understanding of motors and dynamos. In physics, a simple generator or machine for transforming mechanical energy into electrical energy. A dynamo in basic form consists of a powerful field magnet between the poles of which a suitable conductor, usually in the form of a coil (armature), is rotated. The magnetic lines of force are cut by the rotating wire coil, which induces a current to flow through the wire. The mechanical energy of rotation is thus converted into an electric current in the armature. Present-day dynamos work on the principles described by English physicist Michael Faraday in 1830, that an electromotive force is developed in a conductor when it is moved in a magnetic field. The dynamo that powers the lights on a bicycle is an example of an alternator, that is, it produces alternating current (AC).

How does dynamo work? But at the lowest level, if you move a conductor such as wire across a magnetic field, it generates a current in the wire. All dynamos are just different way of packaging up a lot of wires and moving them fast in a magnetic field. There are lots of subtleties, but the underlying physics is the same uses a permanent magnet which is rotated by a crank. The spinning magnet is positioned so that its north and south poles passed by a piece of iron wrapped with wire. It was discovered that the spinning magnet produced a pulse of current in the wire each time a pole passed the coil. Furthermore, the north and south poles of the magnet induce currents in opposite directions. By adding a commutator, it is possible to convert the alternating current to direct current. In my view, and in the view of many bicycle safety experts, dynamos are usually not an attractive option. This is for reasons of both cost and performance. Decent dynamo light sets are much more costly than decent battery powered lights, and the battery powered lights have vastly superior illumination than even the most expensive dynamo powered system. The problem is that a dynamo driven by a bicycle is very limited in the amount of power that can be generated.

The Attraction to Dynamo Powered Lights The attraction of dynamo powered lights is obvious; you are selfsufficient and there is no limit to the duration that the lights can be used. Some individuals believe that having to rely on mains power for bicycle lighting is somehow cheating. Purists may be willing to spend the additional money for a high end, 6 watt, dynamo system, or live with the lower performance and lower safety provided by a 3 watt dynamo powered system. Of course a few of these people will hotly dispute the contention that a 3 watt system is less safe than a higher power system, but the bicycle safety experts do not agree with this contention. In well lit cities where the cyclist is familiar with their route, a dynamo system is often sufficient. However due to the power generation limits of a bicycle dynamo, it simply is not possible to generate enough power for lights that are bright enough for use on dark or unfamiliar routes. Another factor is that as we age, our night vision deteriorates, and brighter lighting is necessary for safety. Personally, I do own a dynamo. It's fine for going around a familiar town at night, and eliminates the need to worry about batteries. However I would never use it on dark or unfamiliar routes.

Watts worth of Lights The less expensive 3W generators are used to power a 2.4W headlight and 0.6W tail light. However you can eliminate the taillight and increase the headlight to 3W. Then add a battery powered rear xenon strobe or Real Lite LED flasher. You should also add a front xenon strobe if using a 2.4-3W headlight; this will solve the "being seen" problem inherent to the very low power headlamps, a 2.4-3W light is not bright enough to stand out in a sea of bright lights. A 6 volt, 2.4W spot beam headlamp, as typically used with lower cost generator lights, is certainly better than no lighting at all. It is not as nearly as good as a system that provides both wide angle and spot beam coverage at higher candlepower. The 2.4W spot beam is especially good for illuminating the road directly in front of the bicycle (for a short distance, suitable for slow riding), but is especially poor in terms of being seen, where a wider beam pattern is necessary, and is not good for high speed riding. As stated above, if using a 2.4-3W dynamo powered headlamp then consider adding at least a battery powered clear xenon strobe to the front of your bicycle as well.

Introduction The main purpose to explain how to construct a high performance battery powered lighting system. Promote dynamo powered bicycle lighting systems. While I also use dynamo lights on occasion, I believe that it's important to understand the facts regarding dynamo systems and battery based systems, so you can choose the most appropriate lighting system for your needs. These e-mails and posts show that there are some dynamo users who's views on dynamo lights center around the idea that "I use them, so they must be fine, and anyone that disagrees with me is wrong because I say so." When people are so defensive, it's because they are insecure about their own choices. I decided to add this section on dynamo powered lights, so the reader can get an unbiased evaluation of the pros and cons of dynamo powered lights.

Description the generating of a current by means of a dynamo-electric machine was briefly considered. The reversal of the direction of the current induced by the motion of the coil of wire, as illustrated in Fig. 25, is true of all the coils of wire comprising in part the armature of a dynamo. This is further illustrated in Fig. 26, which shows the ends of the wire coil C - C connected with two semicircular pieces of brass, A and B, representing the commutator, which are in contact with flat pieces of copper, E and F, representing the brushes of a dynamo. Assuming that the coil of wire is revolving clockwise, and cutting the lines of force from the N to the S poles of the magnet, a current induced in the part of the coil C is in the reverse direction from that in the part C, and only requires a closed circuit to flow around

the coil in the direction shown by the arrows. As the coil continues to revolve until the position of the parts C and C are reversed, the current still flows around the circuit L in the same direction. The direction of the current in the coil has been reversed, but the pieces E and F are now in contact with different brushes, so the current still flows in the same direction around the main circuit. By having a large number of coils of wire in the armature and a corresponding number of sections in the commutator, the current in the main circuit is made practicallv uniform, the current from one coil rapidly succeeding that from the preceding coil.

In commercial dynamos the practice is to have from 24 to 50 coils, each coil having several turns of wire, or the equivalent to several turns, as, to save labor, several lengths of insulated wire are wound together and the ends soldered at the proper section of the commutator. The greater the number of coils the more uniform the current, but the size of the machine and its uses regulate the number that are mechanically desirable. The sections of the commutator are insulated from each other by mica or other nonconductor. In addition to the coils of wire in the armature of a dynamo is an iron core, the purpose of which is to make a good magnetic path for the lines of force passing through it from the N to the S pole of the field magnets, as the core concentrates these lines of force, so increasing the number cut by the coils of wire, and consequently increasing the efficiency of the dynamo. The magnets between which the armature revolves are called the field magnets. The function of

the field magnets is to provide the magnetic lines of force, through which the armature coils revolve. They may be permanent magnets or electro-magnets, the latter being universally used when other than very light work is required. The reason for this is that electro-magnets are capable of giving a much more powerful current than permanent magnets.

In the earliest forms of dynamos the field magnets were excited by a current from an outside source; but this form was soon superseded by the self-exciting dynamo. One form, known as the series dynamo, is shown in Fig. 27. The iron cores of the

field magnets, after being once excited, retain a certain amount of magnetism, termed residual magnetism. While small in amount, it is yet sufficient to produce some electro-motive force, so that when the armature revolves, a feeble current is produced, which, passing through the field coils, increases the magnetism, which, in turn, increases the magnetic lines of force and the resulting current from the armature coils. This continues until the armature core and field cores are thoroughly saturated with magnetism, and the dynamo reaches its maximum efficiency. By experiment and calculation the size and wiring of the several parts of a dynamo are carefully determined, tha the greatest output may be obtained from a given expenditure of power, and yet not reach a point where excessive or injurious E. M. F. is generated. The series dynamo is a form not much used, as it is not selfregulating under a varying load. If underloaded, the E. M. F. increases excessively ; if overloaded, it decreases rapidly, - the reverse of which is desirable under those conditions.

The wiring of the field coils is in series with the outside circuit, and the armature and the whole current passes through them. This necessitates a few turns of large wire for the fields. The load of a series dynamo is usually connected in series. Another form of wiring which overcomes certain of the objections of the series dynamo is that known as the shunt-wound dynamo, shown in Fig. 28. In this type the field coils form a shunt to the main circuit, only a portion of the current from the armature passing through them. The current, therefore, is divided or shunted, the larger part going directly to the outside

circuit, and the balance around the field coils. As this latter current is small in amount, the wire for the field coils of a shunt-wound dynamo is small in size, but consists of many turns. The magnetism produced by the field coils is proportional to the current and the turns of wire, ampere turns, as they are called. Thus 10 turns of a large wire carrying 10 amperes is the equal of 100 turns of smaller wire carrying 1 ampere, and each will exert the same magnetizing force. By reducing the size of the wire, the ampere turns of a shunt-wound dynamo is made equal to the ampere turns of a series dynamo of the same size. The amount of energy required to magnetize the fields, and the efficiency of the two types of dynamos under a normal load, should be the same.

The shunt dynamo is more nearly selfregulating under a varying load than a series dynamo, the load being usually in parallel. Therefore, as additional branches in parallel in the main circuit are closed, the resistance falls, and more current is supplied by the armature. This decreases the amount received in the shunt or field coils, thus reducing the magnetism, which in turn slightly reduces the current of the armature, and so regulates the output of the dynamo. A low resistance in the armature is desirable in this type, and also an even strength of magnetism in the fields. To regulate the voltage of a shunt dynamo, a rheostat is generally inserted in the shunt circuit. A rheostat is an instrument containing circuits of varying resistance, with a switch for disconnecting any or all of them. Another type of dynamo which is selfregulating under wide variations of load is that known as the compound dynamo, shown in Fig. 29. This is a combination of the two previous forms of winding. In addition to the shunt winding of the fields,

a few coils of thick wire in series with the main circuit are added. The effect of this is to make the current in the field winding, and consequently the magnetism produced proportional to the current flowing from the armature. The shunt winding maintains the proper voltage and the series winding the volume of current. It is customary, when using this form of dynamo for electric lighting work, to have the series winding slightly in excess of the theoretical requirements, that the voltage of the current may be fully maintained at all parts of the main circuit. This is called over compounding. The various parts of the above types of dynamos will be more fully considered in subsequent chapters

The "Team Dynamo" is a new type of group exercise. The Team works together to drive a generator to help power the gym. We are installing the first one in Portland, OR in late August. The gym owner, Adam Boesel, is trying to make the greenest gym in the world and is a believer in "Human Power". The 4 place Team Dynamo can generate from 150-450 watts per hour depending on the fitness level of the Team.

This is enough power for the gym's TV's and stereo. "Putting Humans to WORK!"

L.E.D.
(LIGHT EMITTING DIODE) Light emitting diode (LED ) is basically a P-N junction semiconductor diode particularly designed to emit visible light. There are infra-red emitting LEDs which emit invisible light. The LEDs are now available in many colour red, green and yellow,. A normal LED emit at 2.4V and consumes MA of current. The LEDs are made in the form of flat tiny P-N junction enclosed enclosed in a semi-spherical dome made up of clear colured epoxy resin. The dome of a LED acts as a lens and diffuser of light. The diameter of the base is less than a quarter of an inch. The actual diameter varies somewhat with different makes. The common circuit symbols for the LED are shown in fig. 1. It is similar to the conventional rectifier diode symbol with two arrows pointing out. There are two leads- one for anode and the other for cathode. LEDs often have leads of dissimilar length and the shorter one is the cathode. This is not strictly adhered to by all manufacturers. Sometimes the cathode side has a flat base. If there is doubt, the polarity of the diode should be identified. A simple bench method is to use the ohmmeter incorporating 3-volt cells for ohmmeter function. When connected with the ohmmeter: one way there will be no deflection and when connected the other way round there will be a large deflection of a pointer. When this occurs the anode lead is connected to the negative of test lead and cathode to the positive test lead of the ohmmeter.

External resistor. Unless an LED is of the ‘constant-current type’ (incorporating an integrated circuit regulator—see Unit 20.4—for use on a 2 to 18 V d.c. or a. c. supply), it must have an external resistor R connected in series to limit the forward current which, typically, may be 10 mA (0.01 A). Taking the voltage drop (Vf) across a conducting LED to be about 107 V, R can be calculated approximately from:
(ii)

(supply voltage – 1.7) V R = —————————————————— 0.01A For example, on a 5 V supply, R = 3.3/0.01 = 330 Ohm.

(i) Action. An LED consists of a junction diode made form the semiconducting compound gallium arsenide phosphide. It emits light when forward biased, the colour depending on the composition and impurity content of the compound. At present red, yellow and green LEDs are available. When a p-n junction diode is forward biased, electrons move across the junction from the n-type side to the p-type side where they recombine with holes near the junction. The same occurs with holes going across the junction from the p-type side. Every recombination results in the release of a certain amount

of energy, causing, in most semiconductors, a temperature rise. In gallium arsenide phosphide some of the energy is emitted as light which gets out of the LED because the junction is formed very close to the surface of the material. An LED does not light when reverse biased and if the bias is 5 V or more it may be damaged.

External resistor. Unless an LED is of the ‘constant-current type’ (incorporating an integrated circuit regulator—see Unit 20.4—for use on a 2 to 18 V d.c. or a. c. supply), it must have an external resistor R connected in series to limit the forward current which, typically, may be 10 mA (0.01 A). Taking the voltage drop (Vf) across a conducting LED to be about 107 V, R can be calculated approximately from:
(ii)

(supply voltage – 1.7) V R = —————————————————— 0.01A For example, on a 5 V supply, R = 3.3/0.01 = 330 Ohm.

(iii) Decimal display. Many electronic calculators, clocks, cash registers and measuring instruments have seven-segment red or green LED displays as numerical indicators (Fig. 9.18(a)). Each segment is an LED and depending on which segments are energized, the display lights up the numbers 0 to 9 as in Fig. 9.18(b). Such displays are usually designed to work on a 5 V supply. Each segment needs a separate current-limiting resistor and all the cathodes (or anodes) are joined together to form a common connection

AUTOMATIC NIGHT LIGHT

Here used Light Dependent Resistor for bulb on automatically in night and is off in day light. When light falls on LDR then LDR shows a low resistance and in dark LDR shows a high resistance. Our requirement is to switch on the circuit in night (dark). For this purpose we use two transistors. Both are NPN transistors. One NPN (T1) switches on the bulb and second transistors (2) switches off the bulb. LDR is connected to the base of T2. When light falls on LDR then LDR shows a low resistance and transistor T2 gives a –ve cut off voltage to base of T1. by receiving a-ve cut off.T1 is cut off and output bulb is off, if we want to switch on the transistor T1 then it is possible by removing the cut off voltage from the base of T1.cut off voltage supplied by transistor T2, if we cover the LDR by hand then LDR shows a high resistance and transistor T2 is cut off. When transistor T2 is cut off then transistor T1 is switch on automatically.

RELAY
Relay is a common, application of application of electromagnetism. It uses an electromagnet made from an iron rod wound with hundreds of fine copper wire. When electricity is applied to the wire, the rod become magnetic. A movable contact arm above the rod is then pulled toward, a small spring pulls the contract arm away from the rod until it close, a second switch contact. By means of relay, a current circuit can be broken or closd in one circuit as a result of a current in another circuit. Relays can have several poles and contacts. The types of contacts could be normally open and normally closed. One closure of the relay can turn on the same normally open contacts; can turn off the other normally closed contacts A relay is a switch worked by an electromagnet. It is useful if we want a small current in one circuit to control another circuit containing a device such as a lamp or electric motor which requires a large current, or if we wish several different switch contacts to be operated simultaneously. The structure of relay and its symbol are shown in figure. When the controlling current flows through the coil, the soft iron core is magnetized and attracts the Lshaped soft iron armature. This rocks on its pivot and opens, closes or changes over, the electrical contacts in the circuit being controlled.

The current needed to operate a relay is called the pull-in current and the drop-out current is the current in the coil when the relay just stops working. If the coil resistance R of a relay is 100 and its operating voltage V is 6V, the pull-in current I is given by:

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