sivaji ganesh diploma.docx

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FOOT STEP POWER GENERATION SYSTEM FOR RURAL ENERGY APPLICATIION TO RUN AC & DC LOADS

Foot Step Power Generation system for rural energy application to run AC and DC loads

INDEX

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TOPICS

CHAPTER 1: INTRODUCTION

1.1 Introduction to the project ……………………………………………….41.2 Project overview…………………………………………………………..5

CHAPTER 2: PROJECT DESCRIPTION…………………………………...6

CHAPTER 3: HARDWARE DESCRIPTION

3.1 Foot step arrangement…………………………………………………….7

3.2 Rack & pinion and chain sprocket arrangement………………………...7

3.3 PMDC generator…………………………………………………………..10

3.4 Battery……………………………………………………………………...14

3.5 Inverter…………………………………………………………………….15

3.6 Light load…………………………………………………………………...17

CHAPTER 4: HARDWARE COMPONENTS

4.1 Resistors……………………………………………………………………..20

4.2 Capacitors…………………………………………………………………...21

4.3 Diodes………………………………………………………………………..21

4.4 LED…………………………………………………………………………22

4.5 Switches and Pushbuttons…………………………………………………23

4.6 Power supply………………………………………………………………..24

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4.6.1 Transformer………………………………………………………….

4.6.2 Rectifiers………………………………………………………………

4.6.3 Capacitor filter……………………………………………………….

4.6.4 Voltage regulator……………………………………………………..

4.7 Power transistor…………………………………………………………….

4.8 Tank circuit…………………………………………………………………

CHAPTER 5: ADVANTAGES AND APPLICATIONS………………………

CHAPTER 6: KIT PHOTO REPRESENTATION……………………………

CHAPTER 7:

І. RESULTS……………………………………………………………………….

ІІ CONCLUSION…………………………………………………………………

ІІІ BIBLIOGRAPHY……………………………………………………….

CHAPTER 1: INTRODUCTION

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1.1. Introduction to the project

Man has needed and used energy at an increasing rate for his sustenance and

wellbeing ever since he came on the earth a few million years ago. Primitive man required

energy primarily in the form of food. He derived this by eating plants or animals, which he

hunted. With the passage of time, man started to cultivate land for agriculture. He added anew

dimension to the use of energy by domesticating and training animals to work for him. With

further demand for energy, man began to use the wind for sailing ships and for driving

windmills, and the force of falling water to turn water for sailing ships and for driving windmills,

and the force of falling water to turn water wheels. Till this time, it would not be wrong to

say that the sun was supplying all the energy needs of man either directly or indirectly and that

man was using only renewable sources of energy.

Other people have developed piezo-electric (mechanical-to-electrical) surfaces in the

past, but the Crowd Farm has the potential to redefine urban space by adding a sense of fluidity

and encouraging people to activate spaces with their movement. The Crowd Farm floor

is composed of standard parts that are easily replicated but it is expensive to produce at this

stage. This technology would facilitate the future creation of new urban landscapes athletic fields

with a spectator area, music halls, theatres, nightclubs and a large gathering space for

rallies, demonstrations and celebrations, railway stations, bus stands, subways, airports etc. like

capable of harnessing human locomotion for electricity generation.

1.2. Project overview:

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Proposal for the utilization of waste energy of foot power with human locomotion is very

much relevant and important for highly populated countries like India and China where the

roads, railway stations, bus stands, temples, etc. are all over crowded and millions of people

move around the clock. This whole human/bioenergy being wasted if can be made possible for

utilization it will be great invention and crowd energy farms will be very useful energy sources

in crowded countries. Walking across a "Crowd Farm," floor, then, will be a fun for idle people

who can improve their health by exercising in such farms with earning. The electrical energy

generated at such farms will be useful for nearby applications.

CHAPTER 2: PROJECT DESCRIPTION

Upper plate

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CHAPTER 3: HARDWARE DESCRIPTION

3.1 Foot step arrangement

Rack &Pinion Generator

Lower plate

AC ripple neutralizer

Unidirectional Current Controller

Rechargeable Battery INVERTER

Light

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WORKING OF FOOT STEP GENERATOR:

Step1: when force is applied on the plate by virtue on stamping on the plate the force spring gets compressed

Step2: the rack here moves vertically down

Step3: The pinion meshed with the rack gear results in circular motion of the pinion gear

Step4: for one full compression the pinion Moves 1semicircle

Step5: when the force applied on the plate released the pinion reverses and moves another semi-circle

Step6: the generator attached to the pinion hence results in the sinusoidal waveform (for single Generator)

3.2 Rack And Pinion and chain sprocket arrangement

DESCRIPTION:

Spring design:

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FL=215

O/d=Φ40

W/d=Φ5

Spring constant: The spring constant k is function of the spring geometry and the spring material's shear

modulus G,a

Where G is found from the material's elastic modulus E and Poisson ratio n,

And D is the mean diameter of the spring (measured from the centers of the wire cross-sections),

The distance between adjacent spring coils (defined as the coil pitch) is found by dividing the spring free length by the number of active coils,

The rise angle of the spring coils (the angle between the coils and the base of the spring) is found from the arctangent of the coil-pitch divided by the spring circumference,

The solid height of the spring is found by summing the widths of all the spring coils. The total number of spring coils is equal to the active coils in the spring interior plus the 2 coils at the spring ends

The length of wire needed to make the spring is found from,

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Spring Force and Stress:The maximum force the spring can take occurs when the spring is deformed all the way to its solid height,

The maximum shear stress in the spring associated with the maximum force is given by,

Where W is the Wahl correction factor (accounting for spring curvature stress) and C is the spring index (essentially an aspect ratio of the spring cross-section),

Spring ResonanceFinally, the lowest resonant frequency (in Hz) of the spring is found from the simple equation,

Where k is the spring constant from above and M is the spring mass. The spring mass M can be found by weighing the spring, or by finding the spring volume and multiplying by its material density,

We can express the spring's lowest resonance in terms of basic spring geometry if we substitute for k and M in the equation for fres (and then eliminate Lwire). Doing so gives,

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For springs with small rise angles and several active coils we can make the approximation,

If we also allow the approximation,

We can then simplify the resonant frequency formula to a form that can be found in several reference books,

3.3. PMDC Generator

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GeneratorConstruction:

Simple loop generator is having a single-turn rectangular copper coil rotating about its own axis

in a magnetic field provided by either permanent magnet or electro magnets. In case of without

commutator the two ends of the coil are joined to slip ringswhich are insulated from each other

and from the central shaft.Two collecting brushes ( of carbon or copper) press against the slip

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rings.Their function is to collect the current induced in the coil. In this case the current waveform

we obtain is alternating current ( you can see in fig). In case of with commutator the slip rings

are replaced by split rings.In this case the current is unidirectional.

Components of a generator:

Rotor: In its simplest form, the rotor consists of a single loop of wire made to rotate within a

magnetic field. In practice, the rotor usually consists of several coils of wire wound on an

armature.

Armature: The armature is a cylinder of laminated iron mounted on an axle. The axle is carried

in bearings mounted in the external structure of the generator. Torque is applied to the axle to

make the rotor spin.

Coil: Each coil usually consists of many turns of copper wire wound on the armature. The two

ends of each coil are connected either to two slip rings (AC) or two opposite bars of a split-ring

commutator (DC).

Stator: The stator is the fixed part of the generator that supplies the magnetic field in which the

coils rotate. It may consist of two permanent magnets with opposite poles facing and shaped to

fit around the rotor. Alternatively, the magnetic field may be provided by two electromagnets.

Field electromagnets: Each electromagnet consists of a coil of many turns of copper wire

wound on a soft iron core. The electromagnets are wound, mounted and shaped in such a way

that opposite poles face each other and wrap around the rotor.

Brushes:The brushes are carbon blocks that maintain contact with the ends of the coils via the

slip rings (AC) or the split-ring commutator (DC), and conduct electric current from the coils to

the external circuit.

Working:

The commutator rotates with the loop of wire just as the slip rings do with the rotor of an

AC generator. Each half of the commutator ring is called a commutator segment and is insulated

from the other half. Each end of the rotating loop of wire is connected to a commutator segment.

Two carbon brushes connected to the outside circuit rest against the rotating commutator. One

brush conducts the current out of the generator, and the other brush feeds it in. The commutator

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is designed so that, no matter how the current in the loop alternates, the commutator segment

containing the outward-going current is always against the "out" brush at the proper time. The

armature in a large DC generator has many coils of wire and commutator segments. Because of

the commutator, engineers have found it necessary to have the armature serve as the rotor(the

rotating part of an apparatus) and the field structure as the stator (a stationary portion enclosing

rotating parts)

3.4. Battery

RECHARGEBLE BATTERIES:

A rechargeable battery or storage battery is a group of one or more electrochemical

cells. They are known as secondary cells because their electrochemical reactions are electrically

reversible. Rechargeable batteries come in many different shapes and sizes, ranging anything

from a button cell to megawatt systems connected to stabilize an electrical distribution network.

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Several different combinations of chemicals are commonly used, including: lead-acid, nickel

cadmium(NiCad), nickel metal hydride (Nigh), lithium ion (Li-ion), and lithium ion polymer (Li-

ion polymer).

Fig 2.22: Rechargeable Batteries

Rechargeable batteries have lower total cost of use and environmental impact than

disposable batteries. Some rechargeable battery types are available in the same sizes as

disposable types. Rechargeable batteries have higher initial cost, but can be recharged very

cheaply and used many times.

Rechargeable batteries are used for automobile starters, portable consumer devices,

light vehicles (such as motorized wheelchairs, golf carts, electric bicycles, and electric forklifts),

tools, and uninterruptible power supplies. Emerging applications in hybrid electric

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vehicles and electric vehicles are driving the technology to reduce cost and weight and increase

lifetime. Normally, new rechargeable batteries have to be charged before use; newer low self-

discharge batteries hold their charge for many months, and are supplied charged to about 70% of

their rated capacity.

Grid energy storage applications use rechargeable batteries for load leveling, where they store

electric energy for use during peak load periods, and for renewable uses, such as storing power

generated from photovoltaic arrays during the day to be used at night. By charging batteries

during periods of low demand and returning energy to the grid during periods of high electrical

demand, load-leveling helps eliminate the need for expensive peaking power plants and

helps amortize the cost of generators over more hours of operation.

The US National Electrical Manufacturers Association has estimated that U.S.

demand for rechargeable batteries is growing twice as fast as demand for non -rechargeable.

3.5. Inverter

An inverter is an electrical device that converts direct current (DC) to alternating

current (AC); the converted AC can be at any required voltage and frequency with the use of

appropriate transformers, switching, and control circuits. Solid-state inverters have no moving

parts and are used in a wide range of applications, from small switching power supplies in

computers, to large electric utility high-voltage direct current applications that transport bulk

power. Inverters are commonly used to supply AC power from DC sources such as solar

panels or batteries.

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Fig 2.26: Inverter

There are two main types of inverter. The output of a modified sine wave inverter

is similar to a square wave output except that the output goes to zero volts for a time before

switching positive or negative. It is simple and low cost (~$0.10USD/Watt) and is compatible

with most electronic devices, except for sensitive or specialized equipment, for example

certain laser printers. A pure sine wave inverter produces a nearly perfect sine wave output

(<3% total harmonic distortion) that is essentially the same as utility-supplied grid power. Thus it

is compatible with all AC electronic devices. This is the type used in grid-tie inverters. Its design

is more complex, and costs 5 or 10 times more per unit power (~$0.50 to $1.00USD/Watt).[1] The

electrical inverter is a high-power electronic oscillator. It is so named because early mechanical

AC to DC converters were made to work in reverse, and thus were "inverted", to convert DC to

AC. The inverter performs the opposite function of a rectifier.

3.6. Light Loads

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A bulb is a short stem with fleshy leaves or leaf bases. The leaves often function

as food storage organs during dormancy .

A bulb's leaf bases generally do not support leaves, but contain food reserves to enable

the plant to survive adverse conditions. The leaf bases may resemble scales, or they may overlap

and surround the center of the bulb as with the onion. A modified stem forms the base of the

bulb, and plant growth occurs from this basal plate. Roots emerge from the underside of the base,

and new stems and leaves from the upper side.

Other types of storage organs (such as corms, rhizomes, and tubers) are sometimes

erroneously referred to as bulbs. The correct term for plants that form 0underground storage

organs, including bulbs as well as tubers and corms, is geophytes.

Some epiphytic orchids (family Orchidaceous) form above-ground storage organs called pseudo

bulbs that superficially resemble bulbs.

Incandescent

These are the standard bulbs that most people are familiar with. Incandescent bulbs work

by using electricity to heat a tungsten filament in the bulb until it glows. The filament is either in

a vacuum or in a mixture of argon/nitrogen gas. Most of the energy consumed by the bulb is

given off as heat, causing its Lumens per Watt performance to be low. Because of the filament's

high temperature, the tungsten tends to evaporate and collect on the sides of the bulb. The

inherent imperfections in the filament causes it to become thinner unevenly. When a bulb is

turned on, the sudden surge of energy can cause the thin areas to heat up much faster than the

rest of the filament, which in turn causes the filament to break and the bulb to burn out.

http://en.wikipedia.org/wiki/Pseudobulb

http://en.wikipedia.org/wiki/Pseudobulb

http://en.wikipedia.org/wiki/Orchidaceae

http://en.wikipedia.org/wiki/Orchid

http://en.wikipedia.org/wiki/Epiphytic

http://en.wikipedia.org/wiki/Geophyte

http://en.wikipedia.org/wiki/Corm

http://en.wikipedia.org/wiki/Tuber

http://en.wikipedia.org/wiki/Tuber

http://en.wikipedia.org/wiki/Rhizome

http://en.wikipedia.org/wiki/Corm

http://en.wikipedia.org/wiki/Root

http://en.wikipedia.org/wiki/Basal_plate

http://en.wikipedia.org/wiki/Plant_stem

http://en.wikipedia.org/wiki/Dormancy

http://en.wikipedia.org/wiki/Storage_organ

http://en.wikipedia.org/wiki/Food

http://en.wikipedia.org/wiki/Leaf

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Incandescent bulbs produce a steady warm, light that is good for most household applications. A

standard incandescent bulb can last for 700-1000 hours, and can be used with a dimmer. Soft

white bulbs use a special coating inside the glass bulb to better diffuse the light; but the light

color is not changed.

Halogen

Halogen bulbs are a variation of incandescent bulb technology. These bulbs work by

passing electricity through a tungsten filament, which is enclosed in a tube containing halogen

gas. This halogen gas causes a chemical reaction to take place which removes the tungsten from

the wall of the glass and deposits it back onto the filament. This extends the life of the bulb. In

order for the chemical reaction to take place, the filament needs to be hotter than what is needed

for incandescent bulbs. The good news is that a hotter filament produces a brilliant white light

and is more efficient (more lumens per watt).

The bad news is that a hotter filament means that the tungsten is evaporating that much

faster. Therefore a denser, more expensive fill gas (krypton), and a higher pressure, are used to

slow down the evaporation. This means that a thicker, but smaller glass bulb (envelope) is

needed, which translates to a higher cost. Due to the smaller glass envelope (bulb), the halogen

bulb gets much hotter than other bulbs. A 300 watt bulb can reach over 300 degrees C. Therefore

attention must be paid to where halogen bulbs are used, so that they don't accidentally come in

contact with flammable materials, or burn those passing by.

Care must be taken not to touch the glass part of the bulb with our fingers. The oils from

our fingers will weaken the glass and shorten the bulb’s life. Many times this causes the bulb to

burst when the filament finally burns out.

To summarize, the halogen has the advantage of being more efficient (although not by

much) and having longer life than the incandescent bulb. They are relatively small in size and are

dimmable. The disadvantages are that they are more expensive, and burn at a much higher

temperature, which could possibly be a fire hazard in certain areas.

Fluorescent

These bulbs work by passing a current through a tube filled with argon gas and mercury.

This produces ultraviolet radiation that bombards the phosphorous coating causing it to emit

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light (see: “How Fluorescents Work”). Bulb life is very long - 10,000 to 20,000 hours.

Fluorescent bulbs are also very efficient, producing very little heat. A common misconception is

that all fluorescent lamps are neutral or cool in color appearance and do not have very good

color-rendering ability. This is largely due to the fact that historically the "cool white"

fluorescent lamp was the industry standard. It had a very cool color appearance (4200K) and

poor CRI rating. This is simply no longer the case. Regarding color, a wide variety of fluorescent

lamps , using rare-earth tri-phosphor technology, offer superior color rendition and a wide range

of color temperature choices (from 2700K to 5000K and higher). Fluorescent bulbs are ideal for

lighting large areas where little detail work will be done (e.g. basements, storage lockers, etc.).

With the new type bulbs, and style of fixtures coming out, fluorescents can be used in most

places around the home. Most fluorescent bulb cannot be used with dimmers.

That fluorescent bulb need components called ballasts to provide the right amount of

voltage. There are primarily two types - magnetic and electronic. Electronic ballasts solve some

of the flickering and humming problems associated with magnetic ballast, and are more efficient,

but cost more to purchase. Some ballasts need a “starter” to work along with it. Starters are sort

of small mechanical timers, needed to cause a stream of electrons to flow across the tube and

ionize the mercury vapor

On tube type fluorescent bulbs, the letter T designates that the bulb is tubular in shape.

The number after it expresses the diameter of the bulb in eighths of an inch.

CHAPTER 4: HARDWARE COMPONENTS

4.1Resistors

Resistors "Resist" the flow of electrical current. The higher the value of resistance

(measured in ohms) the lower the current will be. Resistance is the property of a component

which restricts theflow of electric current. Energy is used up as the voltage across the component

drives the current through it and this energy appears as heat in the component.

http://www.the12volt.com/ohm/ohmslaw.asp

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Colour Code:

4.2. Capacitors

Capacitors store electric charge. They are used with resistors in timing circuits because it

takes time for a capacitor to fill with charge. They are used to smooth varying DC supplies by

acting as a reservoir of charge. They are also used in filter circuits because capacitors easily pass

AC (changing) signals but they block DC (constant) signals.

Circuit symbol:

Electrolytic capacitors are polarized and they must be connected the correct wayround, at least

one of their leads will be marked + or -.

http://www.kpsec.freeuk.com/powersup.htm#smoothing

http://www.kpsec.freeuk.com/555timer.htm

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Examples:

4.3. Diodes:

Diodes allow electricity to flow in only one direction. The arrow of the circuit symbol

shows the direction in which the current can flow. Diodes are the electrical version of a valve

and early diodes were actually called valves.

Circuit symbol:

Diodes must be connected the correct way round, the diagram may be labeled a or + for anode

and k or - for cathode (yes, it really is k, not c, for cathode!). The

cathode is marked by a line painted on the body. Diodes are

labeled with their code in small print; you may need a magnifying

glass to read this on small signal diodes.

Example:

4.4. LIGHT- EMITTING DIODE (LED):

The longer lead is the anode (+) and the shorter lead is the cathode (&minus). In the

schematic symbol for an LED (bottom), the anode is on the left and the cathode is on the right.

Light emitting diodes are elements for light signalization in electronics.

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They are manufactured in different shapes, colors and sizes. For their low price, low

consumption and simple use, they have almost completely pushed aside other light sources-

bulbs at first place.

It is important to know that each diode will be immediately destroyed unless its current is

limited. This means that a conductor must be connected in parallel to a diode. In order to

correctly determine value of this conductor, it is necessary to know diode’s voltage drop in

forward direction, which depends on what material a diode is made of and what colors it is.

Values typical for the most frequently used diodes are shown in table below: As seen, there are

three main types of LEDs. Standard ones get full brightness at current of 20mA. LowCurrent

diodes get full brightness at ten time’s lower current while Super Bright diodes produce more

intensive light than Standard ones.

Since the 8052 microcontrollers can provide only low input current and since their pins are

configured as outputs when voltage level on them is equal to 0, direct confectioning to LEDs is carried

out as it is shown on figure (Low current LED, cathode is connected to output pin).

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4.5. Switches and Pushbuttons:

A push button switch is used to either close or open an electrical circuit depending on the application.

Push button switches are used in various applications such as industrial equipment control handles,

outdoor controls, mobile communication terminals, and medical equipment, and etc. Push button switches

generally include a push button disposed within housing. The push button may be depressed to cause

movement of the push button relative to the housing for directly or indirectly changing the state of an

electrical contact to open or close the contact. Also included in a pushbutton switch may be an actuator,

driver, or plunger of some type that is situated within a switch housing having at least two contacts in

communication with an electrical circuit within which the switch is incorporated.

Typical actuators used for contact switches include spring loaded force cap actuators that reciprocate

within a sleeve disposed within the canister. The actuator is typically coupled to the movement of the cap

assembly, such that the actuator translates in a direction that is parallel with the cap. A push button switch

for a data input unit for a mobile communication device such as a cellular phone, a key board for

a personal computer or the like is generally constructed by mounting a cover member directly on a circuit

board. Printed circuit board (PCB) mounted pushbutton switches are an inexpensive means of providing

an operator interface on industrial control products. In such push button switches, a substrate which

includes a plurality of movable sections is formed of a rubber elastomeric. The key top is formed on a top

surface thereof with a figure, a character or the like by printing, to thereby provide a cover member. Push

button switches incorporating lighted displays have been used in a variety of applications. Such switches

are typically comprised of a pushbutton, an opaque legend plate, and a back light to illuminate the legend

plate.

4.6. Block Diagram for Power Supply:

http://www.electronics-manufacturers.com/products/relays-switches/push-button-switch/



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Figure: Power Supply

Description:

4.6.1 Transformer

A transformer is a device that transfers electrical energy from one circuit to another

through inductively coupled conductors—the transformer's coils. A varying current in the first or

primary winding creates a varying magnetic flux in the transformer's core, and thus a varying

magnetic field through the secondary winding. This varying magnetic field induces a varying

electromotive force (EMF) or "voltage" in the secondary winding. This effect is called mutual

induction.

Figure: Transformer Symbol

(or)

Transformer is a device that converts the one form energy to another form of energy like a

transducer.

http://en.wikipedia.org/wiki/Volt

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Figure: Transformer

Basic Principle

A transformer makes use of Faraday's law and the ferromagnetic properties of an iron

core to efficiently raise or lower AC voltages. It of course cannot increase power so that if the

voltage is raised, the current is proportionally lowered and vice versa.

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Figure: Basic Principle

Transformer Working

A transformer consists of two coils (often called 'windings') linked by an iron core, as

shown in figure below. There is no electrical connection between the coils; instead they are

linked by a magnetic field created in the core.

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Figure: Basic Transformer

Transformers are used to convert electricity from one voltage to another with minimal

loss of power. They only work with AC (alternating current) because they require a changing

magnetic field to be created in their core. Transformers can increase voltage (step-up) as well as

reduce voltage (step-down).

Alternating current flowing in the primary (input) coil creates a continually changing

magnetic field in the iron core. This field also passes through the secondary (output) coil and the

changing strength of the magnetic field induces an alternating voltage in the secondary coil. If

the secondary coil is connected to a load the induced voltage will make an induced current flow.

The correct term for the induced voltage is 'induced electromotive force' which is usually

abbreviated to induced e.m.f.

The iron core is laminated to prevent 'eddy currents' flowing in the core. These are

currents produced by the alternating magnetic field inducing a small voltage in the core, just like

that induced in the secondary coil. Eddy currents waste power by needlessly heating up the core

but they are reduced to a negligible amount by laminating the iron because this increases the

electrical resistance of the core without affecting its magnetic properties.

Transformers have two great advantages over other methods of changing voltage:

1. They provide total electrical isolation between the input and output, so they can be safely

used to reduce the high voltage of the mains supply.

2. Almost no power is wasted in a transformer. They have a high efficiency (power out /

power in) of 95% or more.

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Classification of Transformer

Step-Up Transformer

Step-Down Transformer

Step-Down Transformer

Step down transformers are designed to reduce electrical voltage. Their primary voltage

is greater than their secondary voltage. This kind of transformer "steps down" the voltage applied

to it. For instance, a step down transformer is needed to use a 110v product in a country with a

220v supply.

Step down transformers convert electrical voltage from one level or phase configuration

usually down to a lower level. They can include features for electrical isolation, power

distribution, and control and instrumentation applications. Step down transformers typically rely

on the principle of magnetic induction between coils to convert voltage and/or current levels.

Step down transformers are made from two or more coils of insulated wire wound around

a core made of iron. When voltage is applied to one coil (frequently called the primary or input)

it magnetizes the iron core, which induces a voltage in the other coil, (frequently called the

secondary or output). The turn’s ratio of the two sets of windings determines the amount of

voltage transformation.

Figure: Step-Down Transformer

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An example of this would be: 100 turns on the primary and 50 turns on the secondary, a ratio of 2 to 1.

Step down transformers can be considered nothing more than a voltage ratio device.

With step down transformers the voltage ratio between primary and secondary will mirror the

"turn’s ratio" (except for single phase smaller than 1 kva which have compensated secondary). A

practical application of this 2 to 1 turn’s ratio would be a 480 to 240 voltage step down. Note that

if the input were 440 volts then the output would be 220 volts. The ratio between input and

output voltage will stay constant. Transformers should not be operated at voltages higher than

the nameplate rating, but may be operated at lower voltages than rated. Because of this it is

possible to do some non-standard applications using standard transformers.

Single phase step down transformers 1 KVA and larger may also be reverse connected to

step-down or step-up voltages. (Note: single phase step up or step down transformers sized less

than 1 KVA should not be reverse connected because the secondary windings have additional

turns to overcome a voltage drop when the load is applied. If reverse connected, the output

voltage will be less than desired.)

Step-Up Transformer

A step up transformer has more turns of wire on the secondary coil,which makes a larger induced

voltage in the secondary coil.It is called a step up transformer because the voltage output is larger than the

voltage input.

Step-up transformer 110v 220v design is one whose secondary voltage is greater than its primary

voltage. This kind of transformer "steps up" the voltage applied to it. For instance, a step up transformer

is needed to use a 220v product in a country with a 110v supply.

A step up transformer 110v 220v converts alternating current (AC) from one voltage to

another voltage. It has no moving parts and works on a magnetic induction principle; it can be

designed to "step-up" or "step-down" voltage. So a step up transformer increases the voltage and

a step down transformer decreases the voltage.

http://www.gcsescience.com/pme16.htm

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The primary components for voltage transformation are the step up transformer core and

coil. The insulation is placed between the turns of wire to prevent shorting to one another or to

ground. This is typically comprised of Mylar, nomex, Kraft paper, varnish, or other materials. As

a transformer has no moving parts, it will typically have a life expectancy between 20 and 25

years.

Figure: Step-Up Transformer

Applications

Generally these Step-Up Transformers are used in industries applications only.

Types of Transformer

Mains Transformers

Mains transformers are the most common type. They are designed to reduce the AC

mains supply voltage (230-240V in the UK or 115-120V in some countries) to a safer low

voltage. The standard mains supply voltages are officially 115V and 230V, but 120V and 240V

are the values usually quoted and the difference is of no significance in most cases.

Figure: Main Transformer

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To allow for the two supply voltages mains transformers usually have two separate primary coils

(windings) labeled 0-120V and 0-120V. The two coils are connected in series for 240V (figure

2a) and in parallel for 120V (figure 2b). They must be wired the correct way round as shown in

the diagrams because the coils must be connected in the correct sense (direction):

Most mains transformers have two separate secondary coils (e.g. labeled 0-9V, 0-9V) which may

be used separately to give two independent supplies, or connected in series to create a centre-

tapped coil (see below) or one coil with double the voltage.

Some mains transformers have a centre-tap halfway through the secondary coil and they are

labeled 9-0-9V for example. They can be used to produce full-wave rectified DC with just two

diodes, unlike a standard secondary coil which requires four diodes to produce full-wave

rectified DC.

A mains transformer is specified by:

1. Its secondary (output) voltages Vs.

2. Its maximum power, Pmax, which the transformer can pass, quoted in VA (volt-amp). This

determines the maximum output (secondary) current, Imax...

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...where Vs is the secondary voltage. If there are two secondary coils the maximum

power should be halved to give the maximum for each coil.

3. Its construction - it may be PCB-mounting, chassis mounting (with solder tag

connections) or toroidal (a high quality design).

Audio Transformers

Audio transformers are used to convert the moderate voltage, low current output of an audio

amplifier to the low voltage, high current required by a loudspeaker. This use is called

'impedance matching' because it is matching the high impedance output of the amplifier to the

low impedance of the loudspeaker.

Figure: Audio transformer

Radio Transformers

Radio transformers are used in tuning circuits. They are smaller than mains and audio

transformers and they have adjustable ferrite cores made of iron dust. The ferrite cores can be

adjusted with a non-magnetic plastic tool like a small screwdriver. The whole transformer is

enclosed in an aluminum can which acts as a shield, preventing the transformer radiating too

much electrical noise to other parts of the circuit.

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Figure: Radio Transformer

Turns Ratio and Voltage

The ratio of the number of turns on the primary and secondary coils determines the ratio of the

voltages...

...where Vp is the primary (input) voltage, Vs is the secondary (output) voltage, Np is the number

of turns on the primary coil, and Ns is the number of turns on the secondary coil.

Diodes

Diodes allow electricity to flow in only one direction. The arrow of the circuit symbol shows the

direction in which the current can flow. Diodes are the electrical version of a valve and early

diodes were actually called valves.

Figure: Diode Symbol

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A diode is a device which only allows current to flow through it in one direction. In this

direction, the diode is said to be 'forward-biased' and the only effect on the signal is that there

will be a voltage loss of around 0.7V. In the opposite direction, the diode is said to be 'reverse-

biased' and no current will flow through it.

4.6.2. Rectifiers:

The purpose of a rectifier is to convert an AC waveform into a DC waveform (OR) Rectifier

converts AC current or voltages into DC current or voltage. There are two different rectification

circuits, known as 'half-wave' and 'full-wave' rectifiers. Both use components called diodes to

convert AC into DC.

The Half-wave Rectifier

The half-wave rectifier is the simplest type of rectifier since it only uses one diode, as shown in

figure.

Figure: Half Wave Rectifier

Figure 2 shows the AC input waveform to this circuit and the resulting output. As you can see,

when the AC input is positive, the diode is forward-biased and lets the current through. When

the AC input is negative, the diode is reverse-biased and the diode does not let any current

through, meaning the output is 0V. Because there is a 0.7V voltage loss across the diode, the

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peak output voltage will be 0.7V less than Vs.

Figure: Half-Wave Rectification

While the output of the half-wave rectifier is DC (it is all positive), it would not be

suitable as a power supply for a circuit. Firstly, the output voltage continually varies between 0V

and Vs-0.7V, and secondly, for half the time there is no output at all.

The Full-wave Rectifier

The circuit in figure 3 addresses the second of these problems since at no time is the output

voltage 0V. This time four diodes are arranged so that both the positive and negative parts of the

AC waveform are converted to DC. The resulting waveform is shown in figure 4.

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Figure: Full-Wave Rectifier

Figure: Full-Wave Rectification

When the AC input is positive, diodes A and B are forward-biased, while diodes C and D are

reverse-biased. When the AC input is negative, the opposite is true - diodes C and D are

forward-biased, while diodes A and B are reverse-biased.

While the full-wave rectifier is an improvement on the half-wave rectifier, its output still isn't

suitable as a power supply for most circuits since the output voltage still varies between 0V and

Vs-1.4V. So, if you put 12V AC in, you will 10.6V DC out.

4.6.3. Capacitor Filter:

The capacitor-input filter, also called "Pi" filter due to its shape that looks like the

Greek letter pi , is a type of electronic filter. Filter circuits are used to remove unwanted or

undesired frequencies from a signal.

http://en.wikipedia.org/wiki/Electronic_filter

http://en.wikipedia.org/wiki/Pi_(letter)

http://en.wikipedia.org/wiki/Greek_alphabet

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Figure: Capacitor Filter

A typical capacitor input filter consists of a filter capacitor C1, connected across the rectifier

output, an inductor L, in series and another filter capacitor connected across the load.

1. The capacitor C1 offers low reactance to the AC component of the rectifier output while

it offers infinite reactance to the DC component. As a result the capacitor shunts an

appreciable amount of the AC component while the DC component continues its journey

to the inductor L

2. The inductor L offers high reactance to the AC component but it offers almost zero

reactance to the DC component. As a result the DC component flows through the

inductor while the AC component is blocked.

3. The capacitor C2 bypasses the AC component which the inductor had failed to block. As

a result only the DC component appears across the load RL.

Figure: Centered Tapped Full-Wave Rectifier with a Capacitor Filter

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4.6.4. Voltage Regulator:

A voltage regulator is an electrical regulator designed to automatically maintain a constant

voltage level. It may use an electromechanical mechanism, or passive or active electronic

components. Depending on the design, it may be used to regulate one or more AC or DC

voltages. There are two types of regulator are they.

Positive Voltage Series (78xx) and

Negative Voltage Series (79xx)

78xx:

’78’ indicate the positive series and ‘xx’indicates the voltage rating. Suppose 7805 produces the

maximum 5V.’05’indicates the regulator output is 5V.

79xx:

’78’ indicate the negative series and ‘xx’indicates the voltage rating. Suppose 7905 produces the

maximum -5V.’05’indicates the regulator output is -5V.

These regulators consists the three pins there are

Pin1: It is used for input pin.

Pin2: This is ground pin for regulator

Pin3: It is used for output pin. Through this pin we get the output.

Figure: Regulator

http://en.wikipedia.org/wiki/Direct_current

http://en.wikipedia.org/wiki/Alternating_current

http://en.wikipedia.org/wiki/Mechanism_(technology)

http://en.wikipedia.org/wiki/Voltage

http://en.wikipedia.org/wiki/Regulator_(automatic_control)

http://en.wikipedia.org/wiki/Electricity

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4.7. POWER TRANSISTOR:

In electronics, a transistor is a semiconductor device commonly used to amplify or switch electronic signals. A transistor is made of a solid piece of a semiconductor material, with at least three terminals for connection to an external circuit. A voltage or current applied to one pair of the transistor's terminals changes the current flowing through another pair of terminals. Because the controlled (output) power can be much larger than the controlling (input) power, the transistor provides amplification of a signal. The transistor is the fundamental building block of modern electronic devices, and is used in radio, telephone, computer and other electronic systems. Some transistors are packaged individually but most are found in integrated circuits.

A transistor is basically two diodes with impurity built into the depletion to both diodes. A power transistor is just this transistor built to carry more power and dissipate more power as opposed to a tiny transistor.

4.8. TANK CIRCUIT:

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In many ways a parallel resonance circuit is exactly the same as the series resonance circuit we looked at in the previous tutorial. Both are 3-element networks that contain two reactive components making them a second-order circuit, both are influenced by variations in the supply frequency and both have a frequency point where their two reactive components cancel each other out influencing the characteristics of the circuit. Both circuits have a resonant frequency point.

The difference this time however, is that a parallel resonance circuit is influenced by the currents flowing through each parallel branch within the parallel LC tank circuit. A tank circuit is a parallel combination of L and C that is used in filter networks to either select or reject AC frequencies. Consider the parallel RLC circuit below.

A parallel circuit containing a resistance, R, an inductance, L and a capacitance, C will produce a parallel resonance (also called anti-resonance) circuit when the resultant current through the parallel combination is in phase with the supply voltage. At resonance there will be a large circulating current between the inductor and the capacitor due to the energy of the oscillations.

A parallelresonantcircuit stores the circuit energy in the magnetic field of the inductor and the electric field of the capacitor. This energy is constantly being transferred back and forth between the inductor and the capacitor which results in zero current and energy being drawn from the supply. This is because the corresponding instantaneous values of IL and IC will always be equal and opposite and therefore the current drawn from the supply is the vector addition of these two currents and the current flowing in IR.

In the solution of AC parallel resonance circuits we know that the supply voltage is common for all branches, so this can be taken as our reference vector. Each parallel branch must be treated separately as with series circuits so that the total supply current taken by the parallel circuit is the vector addition of the individual branch currents. Then there are two methods

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available to us in the analysis of parallel resonance circuits. We can calculate the current in each branch and then add together or calculate the admittance of each branch to find the total current.

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CHAPTER:5 ADVANTAGES AND APPLICATIONS

Advantages

Reliable

Economical

Eco-Friendly

Less consumption of Non- renewable energies.

Applications

Foot step generated power can be used for agricultural, home applications, street-1lightening.

Foot step power generation can be used in emergency power failure situations.

Metros, Rural Applications etc.,

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CHAPTER:6 KIT PHOTO REPRESENTATION

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CHAPTER:7

I.RESULTS

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II.CONCLUSION

The project “FOOT STEP POWER GENERATION FOR RURAL ENERGY

APPLICATION TO RUN A.C. AND D.C. LOADS” is successfully tested and implemented

which is the best economical, affordable energy solution to common people. This can be used for

many applications in rural areas where power availability is less or totally absence. As India is a

developing country where energy management is a big challenge for huge population. By using

this project we can drive both AC as well as D.C loads according to the force.

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III.BIBLIOGRAPHY

o www.howstuffworks.com

o www.answers.com

Books referred:

o EMBEDDED SYSTEM BY RAJ KAMAL

o Magazines:

Electronics for you

Electrikindia

www.techno-preneur.net results

www.telegraph.co.uk/.../energy/.../Japan-harnesses-energy-from-foot.

http://www.answers.com/

Documents

sivaji ganesh diploma.docx