Design of Solar Power System for Home Application

8/3/2019 Design of Solar Power System for Home Application

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DESIGN OF SOLAR POWER SYSTEM FOR HOME APPLICATION

ABSTRACT:

In this project, a design of solar cell is presented. A solar cell or photovoltaic cell is a

device which generates electricity directly from visible light by means of the photovoltaic

effect. In order to generate useful power, it is necessary to connect a number of cells together

to form a solar panel, also known as a photovoltaic module. The nominal output voltage of a

solar panel is usually 12 Volts, and they may be used singly or wired together into an array. The

number and size required is determined by the available light and the amount of energy

required.

The design of the simple solar power system right is to ensuring both reliability of supply and

minimum cost.The PV panel systems may have only a few 12 Volt, but in bigger systems 230 or

110 Volts will probably be needed. The output from a photovoltaic (PV) cell is insufficient to

operate a large DC load. A Boost converter is used to transform the low voltage DC generated

by the solar panels into high voltage DC. In many small scale industries and residential a DC

motor is the only source to run a machine. According to our proposed system 40% of the power

consumption of the industries may reduce as well as our system increases the efficiency of the

industries or home applications.

Introduction:

In today's climate of growing energy needs and increasing environmental concern, alternatives

to the use of non-renewable and polluting fossil fuels have to be investigated. One such

alternative is solar energy.

Solar energy is quite simply the energy produced directly by the sun and collected elsewhere,

normally the Earth. The sun creates its energy through a thermonuclear process that converts

about 650,000,000 tons of hydrogen to helium every second. The process creates heat and

electromagnetic radiation. The heat remains in the sun and is instrumental in maintaining the

thermonuclear reaction. The electromagnetic radiation (including visible light, infra-red light,

and ultra-violet radiation) streams out into space in all directions.


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Only a very small fraction of the total radiation produced reaches the Earth. The radiation that

does reach the Earth is the indirect source of nearly every type of energy used today. The

exceptions are geothermal energy, and nuclear fission and fusion. Even fossil fuels owe their

origins to the sun; they were once living plants and animals whose life was dependent upon the

sun.

Much of the world's required energy can be supplied directly by solar power. More still can be

provided indirectly. The practicality of doing so will be examined, as well as the benefits and

drawbacks. In addition, the uses solar energy is currently applied to will be noted.

Due to the nature of solar energy, two components are required to have a functional solar

energy generator. These two components are a collector and a storage unit. The collector

simply collects the radiation that falls on it and converts a fraction of it to other forms of energy

(either electricity and heat or heat alone). The storage unit is required because of the non-

constant nature of solar energy; at certain times only a very small amount of radiation will be

received. At night or during heavy cloudcover, for example, the amount of energy produced by

the collector will be quite small. The storage unit can hold the excess energy produced during

the periods of maximum productivity, and release it when the productivity drops. In practice, a

backup power supply is usually added, too, for the situations when the amount of energy

required is greater than both what is being produced and what is stored in the container.

Methods of collecting and storing solar energy vary depending on the uses planned for the solar

generator. In general, there are three types of collectors and many forms of storage units.

The three types of collectors are flat-plate collectors, focusing collectors, and passive collectors.

Flat-plate collectors are the more commonly used type of collector today. They are arrays of

solar panels arranged in a simple plane. They can be of nearly any size, and have an output that

is directly related to a few variables including size, facing, and cleanliness. These variables all

affect the amount of radiation that falls on the collector. Often these collector panels have

automated machinery that keeps them facing the sun. The additional energy they take in due to


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the correction of facing more than compensates for the energy needed to drive the extra

machinery.

Focusing collectors are essentially flat-plane collectors with optical devices arranged to

maximize the radiation falling on the focus of the collector. These are currently used only in a

few scattered areas. Solar furnaces are examples of this type of collector. Although they can

produce far greater amounts of energy at a single point than the flat-plane collectors can, they

lose some of the radiation that the flat-plane panels do not. Radiation reflected off the ground

will be used by flat-plane panels but usually will be ignored by focusing collectors (in snow

covered regions, this reflected radiation can be significant). One other problem with focusing

collectors in general is due to temperature. The fragile silicon components that absorb the

incoming radiation lose efficiency at high temperatures, and if they get too hot they can even

be permanently damaged. The focusing collectors by their very nature can create much higher

temperatures and need more safeguards to protect their silicon components.

Passive collectors are completely different from the other two types of collectors. The passive

collectors absorb radiation and convert it to heat naturally, without being designed and built to

do so. All objects have this property to some extent, but only some objects (like walls) will be

able to produce enough heat to make it worthwhile. Often their natural ability to convert

radiation to heat is enhanced in some way or another (by being painted black, for example) and

a system for transferring the heat to a different location is generally added.

People use energy for many things, but a few general tasks consume most of the energy. These

tasks include transportation, heating, cooling, and the generation of electricity. Solar energy

can be applied to all four of these tasks with different levels of success.

Heating is the business for which solar energy is best suited. Solar heating requires almost no

energy transformation, so it has a very high efficiency. Heat energy can be stored in a liquid,

such as water, or in a packed bed. A packed bed is a container filled with small objects that can

hold heat (such as stones) with air space between them. Heat energy is also often stored in

phase-changer or heat-of-fusion units. These devices will utilize a chemical that changes phase


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from solid to liquid at a temperature that can be produced by the solar collector. The energy of

the collector is used to change the chemical to its liquid phase, and is as a result stored in the

chemical itself. It can be tapped later by allowing the chemical to revert to its solid form. Solar

energy is frequently used in residential homes to heat water. This is an easy application, as the

desired end result (hot water) is the storage facility. A hot water tank is filled with hot water

during the day, and drained as needed. This application is a very simple adjustment from the

normal fossil fuel water heaters.

Swimming pools are often heated by solar power. Sometimes the pool itself functions as the

storage unit, and sometimes a packed bed is added to store the heat. Whether or not a packed

bed is used, some method of keeping the pool's heat for longer than normal periods (like a

cover) is generally employed to help keep the water at a warm temperature when it is not in

use.

Solar energy is often used to directly heat a house or building. Heating a building requires much

more energy than heating a building's water, so much larger panels are necessary. Generally a

building that is heated by solar power will have its water heated by solar power as well. The

type of storage facility most often used for such large solar heaters is the heat-of-fusion storage

unit, but other kinds (such as the packed bed or hot water tank) can be used as well. This

application of solar power is less common than the two mentioned above, because of the cost

of the large panels and storage system required to make it work. Often if an entire building is

heated by solar power, passive collectors are used in addition to one of the other two types.

Passive collectors will generally be an integral part of the building itself, so buildings taking

advantage of passive collectors must be created with solar heating in mind.

These passive collectors can take a few different forms. The most basic type is the incidental

heat trap. The idea behind the heat trap is fairly simple. Allow the maximum amount of light

possible inside through a window (The window should be facing towards the equator for this to

be achieved) and allow it to fall on a floor made of stone or another heat holding material.


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During the day, the area will stay cool as the floor absorbs most of the heat, and at night, the

area will stay warm as the stone re-emits the heat it absorbed during the day.

Another major form of passive collector is thermosyphoning walls and/or roof. With this

passive collector, the heat normally absorbed and wasted in the walls and roof is re-routed into

the area that needs to be heated.

The last major form of passive collector is the solar pond. This is very similar to the solar heated

pool described above, but the emphasis is different. With swimming pools, the desired result is

a warm pool. With the solar pond, the whole purpose of the pond is to serve as an energy

regulator for a building. The pond is placed either adjacent to or on the building, and it will

absorb solar energy and convert it to heat during the day. This heat can be taken into the

building, or if the building has more than enough heat already, heat can be dumped from the

building into the pond.

Solar energy can be used for other things besides heating. It may seem strange, but one of the

most common uses of solar energy today is cooling. Solar cooling is far more expensive than

solar heating, so it is almost never seen in private homes. Solar energy is used to cool things by

phase changing a liquid to gas through heat, and then forcing the gas into a lower pressure

chamber. The temperature of a gas is related to the pressure containing it, and all other things

being held equal, the same gas under a lower pressure will have a lower temperature. This cool

gas will be used to absorb heat from the area of interest and then be forced into a region of

higher pressure where the excess heat will be lost to the outside world. The net effect is that of

a pump moving heat from one area into another, and the first is accordingly cooled.

Besides being used for heating and cooling, solar energy can be directly converted to electricity.

Most of our tools are designed to be driven by electricity, so if you can create electricity

through solar power, you can run almost anything with solar power. The solar collectors that

convert radiation into electricity can be either flat-plane collectors or focusing collectors, and

the silicon components of these collectors are photovoltaic cells.


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Photovoltaic cells, by their very nature, convert radiation to electricity. This phenomenon has

been known for well over half a century, but until recently the amounts of electricity generated

were good for little more than measuring radiation intensity. Most of the photovoltaic cells on

the market today operate at an efficiency of less than 15%; that is, of all the radiation that falls

upon them, less than 15% of it is converted to electricity. The maximum theoretical efficiency

for a photovoltaic cell is only 32.3%, but at this efficiency, solar electricity is very economical.

Most of our other forms of electricity generation are at a lower efficiency than this.

Unfortunately, reality still lags behind theory and a 15% efficiency is not usually considered

economical by most power companies, even if it is fine for toys and pocket calculators. Hope for

bulk solar electricity should not be abandoned, however, for recent scientific advances have

created a solar cell with an efficiency of 28.2%efficiency in the laboratory. This type of cell has

yet to be field tested. If it maintains its efficiency in the uncontrolled environment of the

outside world, and if it does not have a tendency to break down, it will be economical for

power companies to build solar power facilities after all.

Of the main types of energy usage, the least suited to solar power is transportation. While

large, relatively slow vehicles like ships could power themselves with large onboard solar

panels, small constantly turning vehicles like cars could not. The only possible way a car could

be completely solar powered would be through the use of battery that was charged by solar

power at some stationary point and then later loaded into the car. Electric cars that are partially

powered by solar energy are available now, but it is unlikely that solar power will provide the

world's transportation costs in the near future.

Solar power has two big advantages over fossil fuels. The first is in the fact that it is renewable;

it is never going to run out. The second is its effect on the environment.

While the burning of fossil fuels introduces many harmful pollutants into the atmosphere and

contributes to environmental problems like global warming and acid rain, solar energy is

completely non-polluting. While many acres of land must be destroyed to feed a fossil fuel

energy plant its required fuel, the only land that must be destroyed for a solar energy plant is


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the land that it stands on. Indeed, if a solar energy system were incorporated into every

business and dwelling, no land would have to be destroyed in the name of energy. This ability

to decentralize solar energy is something that fossil fuel burning cannot match.

As the primary element of construction of solar panels, silicon, is the second most common

element on the planet, there is very little environmental disturbance caused by the creation of

solar panels. In fact, solar energy only causes environmental disruption if it is centralized and

produced on a gigantic scale. Solar power certainly can be produced on a gigantic scale, too.

Among the renewable resources, only in solar power do we find the potential for an energy

source capable of supplying more energy than is used.

Suppose that of the 4.5x1017

kWh per annum that is used by the earth to evaporate water from

the oceans we were to acquire just 0.1% or 4.5x1014

kWh per annum. Dividing by the hours in

the year gives a continuous yield of 2.90x1010

kW. This would supply 2.4 kW to 12.1 billion

people.

This translates to roughly the amount of energy used today by the average American available

to over twelve billion people. Since this is greater than the estimated carrying capacity of the

Earth, this would be enough energy to supply the entire planet regardless of the population.

Unfortunately, at this scale, the production of solar energy would have some unpredictable

negative environmental effects. If all the solar collectors were placed in one or just a few areas,

they would probably have large effects on the local environment, and possibly have large

effects on the world environment. Everything from changes in local rain conditions to another

Ice Age has been predicted as a result of producing solar energy on this scale. The problem lies

in the change of temperature and humidity near a solar panel; if the energy producing panels

are kept non-centralized, they should not create the same local, mass temperature change that

could have such bad effects on the environment.

Of all the energy sources available, solar has perhaps the most promise. Numerically, it is

capable of producing the raw power required to satisfy the entire planet's energy needs.


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Environmentally, it is one of the least destructive of all the sources of energy. Practically, it can

be adjusted to power nearly everything except transportation with very little adjustment, and

even transportation with some modest modifications to the current general system of travel.

Clearly, solar energy is a resource of the future.

Photovoltaic Cells

Photovoltaic (PV) cells, which convert light directly into electricity, have become commonplace

on devices such as calculators and watches. There are a number of technologies in

development with the aim of making PV more economic for electrical power generation. All use

semiconductor materials like those used in silicon chips.

Photovoltaic (PV) power systems convert sunlight directly into electricity. A residential PVpower system enables a homeowner to generate some or all of their daily electrical energy

demand on their own roof, exchanging daytime excess power for future energy needs (i.e.

nighttime usage). The house remains connected to the electric utility at all times, so any power

needed above what the solar system can produce

is simply drawn from the utility. PV systems can also include battery backup or uninterruptible

power supply (UPS) capability to operate selected circuits in the residence for hours or days

during a utility outage. The purpose of this document is to provide tools and guidelines for the

installer to help ensure that residential photovoltaic power systems are properly specified and

installed, resulting in a system that operates to its design potential. This document sets out key

criteria that describe a quality system, and key design and installation considerations that

should be met to achieve this goal. This document deals with systems located on residences

that are connected to utility power, and does not address the special issues of homes that are

remote from utility power.

In this early stage of marketing solar electric power systems to the residential market, it is

advisable for an installer to work with well established firms that have complete, pre-

engineered packaged solutions that accommodate variations in models, rather than custom

designing custom systems. Once a system designhas been chosen, attention to installation


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detail is critically important. Recent studies have found that 10-20% of new PV installations

have serious installation problems that will result in significantly decreased

performance.

The heart of a PV cell is the interface between two different types of semiconductor. When a

light photon hits a silicon atom in this region, it throws out an electron. The electron can travel

through the n-type semiconductor to metal contacts on the surface. The hole left by the

absence of the electron travels in the opposite direction. Once at the metal contact the

electron flows through an electrical circuit back to meet up with a hole at the other contact.

As it flows through the external circuit, the electron does useful work, like charging a battery, or

operating an electrical appliance. Photovoltaic systems have been reducing in cost, and

increasing in efficiency in recent years. The most efficient commercially available systems can

convert up to 16% of the light energy that strikes them into electrical energy.

Boost converter

A boost converter (step-up converter) is a power converter with an output DC voltage greater

than its input DC voltage. It is a class ofswitching-mode power supply (SMPS) containing at

least two semiconductor switches (a diode and a transistor) and at least one energy storage

element. Filters made ofcapacitors (sometimes in combination with inductors) are normally

added to the output of the converter to reduce output voltage ripple.
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Overview

Power can also come from DC sources such as batteries, solar panels, rectifiers and DC

generators. A process that changes one DC voltage to a different DC voltage is called DC to DC

conversion. A boost converter is a DC to DC converter with an output voltage greater than the

source voltage. A boost converter is sometimes called a step-up converter since it steps up

the source voltage. Since power (P = VI) must be conserved, the output current is lower than

the source current.

A boost converter may also be referred to as a 'Joule thief'. This term is usually used only with

very low power battery applications, and is aimed at the ability of a boost converter to 'steal'

the remaining energy in a battery. This energy would otherwise be wasted since a normal load

wouldn't be able to handle the battery's low voltage.

History

For high efficiency, the SMPS switch must turn on and off quickly and have low losses. The

advent of a commercial semiconductor switch in the 1950s represented a major milestone that

made SMPSs such as the boost converter possible. Semiconductor switches turned on and off

more quickly and lasted longer than other switches such as vacuum tubes and

electromechanical relays. The major DC to DC converters were developed in the early 1960s

when semiconductor switches had become available. The aerospace industrys need for small,

lightweight, and efficient power converters led to the converters rapid development.

Switched systems such as SMPS are a challenge to design since its model depends on whether a

switch is opened or closed. R.D. Middlebrook from Caltech in 1977 published the models for DC

to DC converters used today. Middlebrook averaged the circuit configurations for each switch

state in a technique called state-space averaging. This simplification reduced two systems into

one. The new model led to insightful design equations which helped SMPS growth.
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Applications

Battery powered systems often stack cells in series to achieve higher voltage. However,

sufficient stacking of cells is not possible in many high voltage applications due to lack of space.

Boost converters can increase the voltage and reduce the number of cells. Two battery-

powered applications that use boost converters are hybrid electric vehicles (HEV) and lighting

systems.

The Toyota Prius HEV uses a 500 V motor. Without a boost converter, the Prius would need

nearly 417 cells to power the motor. However, a Prius actually uses only 168 cells and boosts

the battery voltage from 202 V to 500 V. Boost converters also power devices at smaller scale

applications, such as portable lighting systems. A white LED typically requires 3.3 V to emit light,

and a boost converter can step up the voltage from a single 1.5 V alkaline cell to power the

lamp. Boost converters can also produce higher voltages to operate cold cathode fluorescent

tubes (CCFL) in devices such as LCD backlights and some flashlights.

Circuit analysis

Operating principle

The key principle that drives the boost converter is the tendency of an inductor to resist

changes in current. When being charged it acts as a load and absorbs energy (somewhat like a

resistor), when being discharged, it acts as an energy source (somewhat like a battery). The

voltage it produces during the discharge phase is related to the rate of change of current, and not

to the original charging voltage, thus allowing different input and output voltages.
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Fig. 1:Boost converter schematic

Fig. 2: The two configurations of a boost converter, depending on the state of the switch S.

The basic principle of a Boost converter consists of 2 distinct states (see figure 2):

in the On-state, the switch S (see figure 1) is closed, resulting in an increase in the inductor

current;

in the Off-state, the switch is open and the only path offered to inductor current is through the

flyback diode D, the capacitor C and the load R. This results in transferring the energy

accumulated during the On-state into the capacitor.

The input current is the same as the inductor current as can be seen in figure 2. So it is not

discontinuous as in the buck converter and the requirements on the input filter are relaxed

compared to a buck converter.

Continuous mode
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Fig. 3:Waveforms of current and voltage in a boost converter operating in continuous mode.

When a boost converter operates in continuous mode, the current through the inductor (IL) never

falls to zero. Figure 3 shows the typical waveforms of currents and voltages in a converter

operating in this mode. The output voltage can be calculated as follows, in the case of an ideal

converter (i.e. using components with an ideal behaviour) operating in steady conditions:

During the On-state, the switch S is closed, which makes the input voltage (Vi) appear across the

inductor, which causes a change in current (IL) flowing through the inductor during a time period

(t) by the formula:

At the end of the On-state, the increase of IL is therefore:

D is the duty cycle. It represents the fraction of the commutation period T during which the

switch is On. Therefore D ranges between 0 (S is never on) and 1 (S is always on).

During the Off-state, the switch S is open, so the inductor current flows through the load. If we

consider zero voltage drop in the diode, and a capacitor large enough for its voltage to remain

constant, the evolution of IL is:
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Therefore, the variation of IL during the Off-period is:

As we consider that the converter operates in steady-state conditions, the amount of energystored in each of its components has to be the same at the beginning and at the end of a

commutation cycle. In particular, the energy stored in the inductor is given by:

So, the inductor current has to be the same at the start and end of the commutation cycle. This

means the overall change in the current (the sum of the changes) is zero:

This can be written as:

Which in turns reveals the duty cycle to be:

From the above expression it can be seen that the output voltage is always higher than the input

voltage (as the duty cycle goes from 0 to 1), and that it increases with D, theoretically to infinity

as D approaches 1. This is why this converter is sometimes referred to as a step-up converter.

Discontinuous mode
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Fig. 4:Waveforms of current and voltage in a boost converter operating in discontinuous mode.

In some cases, the amount of energy required by the load is small enough to be transferred in a

time smaller than the whole commutation period. In this case, the current through the inductor

falls to zero during part of the period. The only difference in the principle described above is

that the inductor is completely discharged at the end of the commutation cycle (see waveforms

in figure 4). Although slight, the difference has a strong effect on the output voltage equation. It

can be calculated as follows:

As the inductor current at the beginning of the cycle is zero, its maximum value (at t = DT) is

During the off-period, IL falls to zero after T:
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Using the two previous equations, is:

The load current Io is equal to the average diode current (ID). As can be seen on figure 4, the

diode current is equal to the inductor current during the off-state. Therefore the output current

can be written as:

Replacing ILmaxand by their respective expressions yields:

Therefore, the output voltage gain can be written as flow:

Compared to the expression of the output voltage for the continuous mode, this expression is

much more complicated. Furthermore, in discontinuous operation, the output voltage gain not


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only depends on the duty cycle, but also on the inductor value, the input voltage, the switching

frequency, and the output current.

BLOCK DIAGRAM:

HARDWARE DETAILDRIVER CIRCUIT

The driver circuit is supplied using a step down transformer 230V/12V AC .In this project the

driver circuit is mainly used to amplify the pulse output coming from the microcontroller

circuit.The output from pin 1 and 2 of PIC16F877A is passed to the buffer IC CD4050 .The buffer

IC acts as a NOT gate .the output from the buffer IC is passed to the two optocoupler

R1

1k

R2

R3R4

R5

R6

1k

R8

1k

U1

OP-07C/301/TIQ1

BDX37

Q2

Q3

D1

D1N1190

C1

1n

0

FROM MICRO CONTROLLER

1K

100100

100

S

G500mA

230/12VMCT2E


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respectively. The optocoupler is used to isolate the voltages between the main circuit and

microcontroller circuit. This signal is passed to the transistors CK100 and 2N2222 which is

connected in a Darlington pair model. The driver circuit has two legs. First leg is connected to

switch-1 Sm and the second leg is connected to switch-2 Sa. Thus the 5V pulse from the

microcontroller circuit is amplified to 12V and sent to MOSFET switch.

POWER SUPPLY

POWER SUPPLY UNIT

Fig 1: Block diagram of power supply unit

As we all know any invention of latest technology cannot be activated without the source of

power. So it this fast moving world we deliberately need a proper power source which will be

apt for a particular requirement. All the electronic components starting from diode to Intel ICs

only work with a DC supply ranging from -+5v to 0-+12v. We are utilizing for the same, the


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cheapest and commonly available energy source of 230v-50Hz and stepping down, rectifying,

filtering and regulating the voltage. This will be dealt briefly in the forth-coming sections.

STEP DOWN TRANSFORMER

When AC is applied to the primary winding of the power transformer it can either be stepped

down or up depending on the value of DC needed. In our circuit the transformer of 230v/0-12v

is used to perform the step down operation where a 230V AC appears as 12V AC across the

secondary winding. One alteration of input causes the top of the transformer to be positive and

the bottom negative. The next alteration will temporarily cause the reverse. The current rating

of the transformer used in our project is 1A. Apart from stepping down AC voltages, it gives

isolation between the power source and power supply circuitries.

DIODE BRIDGE RECTIFIERS

The ac input from the main supply is stepped down using a 230 /30V step down transformer.

The stepped down AC voltage is converted into dc voltage using a diode bridge rectifier. The

diode bridge rectifier consists of four diodes arranged in two legs. The diodes are connected to

the stepped down AC voltage. For positive half cycle of the ac voltage, the diodes D1 and D4 are

forward biased (ref fig). For negative half cycles diodes D2 and D3 are forward biased. Thus dc

voltage is produced to provide input supply to the DC-DC Converter.

FIG 2.DIODE BRIDGE RECTIFIER


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When the positive half cycle is applied to the diode bridge rectifier, the diodes D1 and D4 are

forward biased. The diodes start conducting and the load current flows through the positive of

the supply, diodeD1, the load, the diode D4 and the negative of the supply. The diode D2 and

D3 are reverse biased and do not conduct. During the negative half cycle, the diodes D1 and D4

areb reverse biased and they stop conducting. The diodes D2 & D3 are forward biased and they

start conducting. The load current flows in the same direction for both the half cycles. Thus the

ac supply given to diode bridge rectifier is converted into pulsating dc.

FILTERING UNIT

Filter circuits which are usually capacitors acting as a surge arrester always follow the rectifier

unit. This capacitor is also called as a decoupling capacitor or a bypassing capacitor, is used not

only to short the ripple with frequency of 120Hz to ground but also to leave the frequency of

the DC to appear at the output. A load resistor R1 is connected so that a reference to the

ground is maintained. C1R1 is for bypassing ripples. C2R2 is used as a low pass filter, i.e. it

passes only low frequency signals and bypasses high frequency signals. The load resistor should

be 1% to 2.5% of the load.

1000f/25v : for the reduction of ripples from the pulsating.

10f/25v : for maintaining the stability of the voltage at the load side.

O, 1f : for bypassing the high frequency disturbances.

VOLTAGE REGULATORS:

The voltage regulators play an important role in any power supply unit. The primary purpose of

a regulator is to aid the rectifier and filter circuit in providing a constant DC voltage to the


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device. Power supplies without regulators have an inherent problem of changing DC voltage

values due to variations in the load or due to fluctuations in the AC liner voltage. With a

regulator connected to the DC output, the voltage can be maintained within a close tolerant

region of the desired output IC7805 is used in this project for providing +12v and 12v DC

supply.

DRIVER CIRCUIT COMPONENTS

The driver circuit is used to amplify the pulses. It consists of three main components they are:

o OPTOCOUPLER

o BUFFER IC

o TRANSISTOR

OPTOCOUPLER

Introduction

There are many situations where signals and data need to be transferred from

one subsystem to another within a piece of electronics equipment, or from one piece of

equipment to another, without making a direct ohmic electrical connection. Often this is

because the source and destination are (or may be at times) at very different voltage levels, like

a microprocessor, which is operating from 5V DC but being used to control a MOSFET that is

switching at a higher voltage. In such situations the link between the two must be an isolated

one, to protect the microprocessor from over voltage damage.Relays can of course provide this

kind of isolation, but even small relays tend to be fairly bulky compared with ICs and many of

todays other miniature circuit components. Because theyre electro-mechanical, relays are also

not as reliable and only capable of relatively low speed operation. Where small size, higher

speed and greater reliability are important, a much better alternative is to use an optocoupler.

These use a beam of light to transmit the signals or data across an electrical barrier, and

achieve excellent isolation. Optocouplers typically come in a small 6-pin or 8-pin IC package, but

are essentially a combination of two distinct devices: an optical transmitter, typically a gallium

arsenide LED (light-emitting diode) and an optical receiver such as a phototransistor or light-

triggered diac. The two are separated by a transparent barrier which blocks any electrical


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current flow between the two, but does allow the passage of light. The basic idea is shown in

Fig.1, along with the usual circuit symbol for an optocoupler. Usually the electrical connections

to the LED section are brought out to the pins on one side of the package and those for the

phototransistor or diac to the other side, to physically separate them as much as possible. This

usually allows optocouplers to withstand voltages of anywhere between 500V and 7500V

between input and output. Optocouplers are essentially, digital or switching devices, so they re

best for transferring either on-off control signals or digital data. Analog signals can be

transferred by means of frequency or pulse-width modulation.

Key Parameters

The most important parameter for most optocouplers is their transfer efficiency, usually

measured in terms of their current transfer ratio or CTR. This is simply the ratio between a

current change in the output transistor and the current change in the input LED that produced

it. Typical values for CTR range from 10% to 50% for devices with an output phototransistor and

up to 2000% or so for those with a Darlington transistor pair in the output. Note, however that

in most devices CTR tends to vary with absolute current level. Typically it peaks at a LED current

level of about 10mA, and falls away at both higher and lower current levels Other optocoupler

parameters include the output transistors maximum collector-emitter voltage rating VCE(max),

which limits the supply voltage in the output circuit; the input LEDs maximum current rating


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IF(max), which is used to calculate the minimum value for its series resistor; and the

optocouplers bandwidth, which determines the highest signal frequency that can be

transferred through it ,determined mainly by internal device construction and the performance

of the output phototransistor. Typical opto-couplers with a single output phototransistor may

have a bandwidth of 200 - 300kHz, while those with a Darlington pair are usually about 10

times lower, at around 20 - 30kHz.

GENERAL DESCRIPTION

In our project the optocoupler is used in the driver circuit. They are used to isolate the voltage

between the main circuit and microcontroller circuit. The pulse is provided to the MOSFET

switch using a microcontroller circuit; this circuit produces a waveform of 5V DC. This pulse is

supplied to MOSFET switch which is supplied by 12V AC as the source and destination voltage is

different they have to be isolated, which is done using optocoupler.

MCT2 OR MCT2E OPTOCOUPLER

Specifications


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Gallium Arsenide Diode Infrared Source Optically Coupled to a Silicon npn Phototransistor

High Direct-Current Transfer Ratio

Base Lead Provided for Conventional Transistor Biasing

High-Voltage Electrical Isolation . . .

1.5-kV or 3.55-kV Rating

Plastic Dual-In-Line Package

High-Speed Switching:

tr = 5 s, tf= 5 s Typical

Designed to be Interchangeable with General Instruments MCT2 and MCT2E

BUFFER ICCD4050

The CD4050BC hex buffers are monolithic complementary MOS (CMOS) integratedcircuits constructed with N- and P-channel enhancement mode transistors. These devices

feature logic level conversion using only one supply voltage (VDD). The input signal high level

(VIH) can exceed the VDD supply voltage when these devices are used for logic level

conversions. These devices are intended for use as hex buffers, CMOS to DTL/ TTL converters,

or as CMOS current drivers, and at VDD = 5.0V, they can drive directly two DTL/TTL loads over

the full operating temperature range.

Connection Diagrams

Pin Assignments for DIP


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Schematic Diagrams

CD4050BC1 of 6 Identical Units

Features

Wide supply voltage range: 3.0V to 15V

Direct drive to 2 TTL loads at 5.0V over full temperature range


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High source and sink current capability

Special input protection permits input voltages greater than VDD

Absolute Maximum Ratings

Supply Voltage (VDD) -0.5V to +18V

Input Voltage (VIN) -0.5V to +18V

Voltage at Any Output Pin (VOUT) -0.5V to VDD + 0.5V

Storage Temperature Range (TS) -65C to +150C

Power Dissipation (PD)

Dual-In-Line 700 mWSmall Outline 500 mW

Lead Temperature (TL)

(Soldering, 10 seconds) 260C

Recommended Operating Conditions

Supply Voltage (VDD) 3V to 15VInput Voltage (VIN) 0V to 15V

Voltage at Any Output Pin (VOUT) 0 to VDD

Operating Temperature Range (TA)

CD4049UBC, CD4050BC -40C to +85C

Note 1: Absolute Maximum Ratings are those values beyond which the safety of the device

cannot be guaranteed; they are not meant to imply that the devices should be operated at

these limits. The table of Recommended Operating Conditions and Electrical Characteristicsprovides conditions for actual device operation.

Note 2: VSS = 0V unless otherwise specified

Typical Applications

CMOS to TLL or CMOS at a Lower VDD


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Applications

CMOS hex inverter/buffer

CMOS to DTL/TTL hex converter

CMOS current sink or source driver

CMOS HIGH-to-LOW logic level converter.

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.

TRANSISTOR AS AN AMPLIFIER

The above common emitter amplifier is designed so that a small change in voltage in (Vin)

changes the small current through the base of the transistor and the transistor's current
http://en.wikipedia.org/wiki/Electronicshttp://en.wikipedia.org/wiki/Semiconductor_devicehttp://en.wikipedia.org/wiki/Electronic_amplifierhttp://en.wikipedia.org/wiki/Electronicshttp://en.wikipedia.org/wiki/Semiconductorhttp://en.wikipedia.org/wiki/Terminalshttp://en.wikipedia.org/wiki/Electric_powerhttp://en.wikipedia.org/wiki/Gainhttp://en.wikipedia.org/wiki/Electronic_devicehttp://en.wikipedia.org/wiki/Radiohttp://en.wikipedia.org/wiki/Telephonehttp://en.wikipedia.org/wiki/Computerhttp://en.wikipedia.org/wiki/Integrated_circuithttp://en.wikipedia.org/wiki/Integrated_circuithttp://en.wikipedia.org/wiki/Computerhttp://en.wikipedia.org/wiki/Telephonehttp://en.wikipedia.org/wiki/Radiohttp://en.wikipedia.org/wiki/Electronic_devicehttp://en.wikipedia.org/wiki/Gainhttp://en.wikipedia.org/wiki/Electric_powerhttp://en.wikipedia.org/wiki/Terminalshttp://en.wikipedia.org/wiki/Semiconductorhttp://en.wikipedia.org/wiki/Electronicshttp://en.wikipedia.org/wiki/Electronic_amplifierhttp://en.wikipedia.org/wiki/Semiconductor_devicehttp://en.wikipedia.org/wiki/Electronics


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amplification combined with the properties of the circuit mean that small swings in Vin produce

large changes in Vout..It is important that the operating parameters of the transistor are chosen

and the circuit designed such that as far as possible the transistor operates within a linear

portion of the graph, such as that shown between A and B, otherwise the output signal will

suffer distortion. Various configurations of single transistor amplifier are possible, with some

providing current gain, some voltage gain, and some both. From mobile phones to televisions,

vast numbers of products include amplifiers for sound reproduction, radio transmission, and

signal processing. The first discrete transistor audio amplifiers barely supplied a few hundred

milliwatts, but power and audio fidelity gradually increased as better transistors became

available and amplifier architecture evolved. Modern transistor audio amplifiers of up to a few

hundred watts are common and relatively in expensive. Some musical instrument amplifier

manufacturers mix transistors and vacuum tubes in the same circuit, as some believe tubes

have a distinctive sound.

GENERAL DESCRIPTION

In our project we use transistor in driver circuit. the transistor is used to amplify the signal pulse

coming from the microcontroller circuit .Here we use two main types of transistor namely

CK100

2N2222

These two transistors are present in the driver circuit which is connected in a darlington pair

circuit.

DARLINGTON PAIR CIRCUIT
http://en.wikipedia.org/wiki/Linearhttp://en.wikipedia.org/wiki/Distortionhttp://en.wikipedia.org/wiki/Mobile_phonehttp://en.wikipedia.org/wiki/Televisionhttp://en.wikipedia.org/wiki/Amplifierhttp://en.wikipedia.org/wiki/Sound_reproductionhttp://en.wikipedia.org/wiki/Transmitterhttp://en.wikipedia.org/wiki/Signal_processinghttp://en.wikipedia.org/wiki/Watthttp://en.wikipedia.org/wiki/Watthttp://en.wikipedia.org/wiki/Signal_processinghttp://en.wikipedia.org/wiki/Transmitterhttp://en.wikipedia.org/wiki/Sound_reproductionhttp://en.wikipedia.org/wiki/Amplifierhttp://en.wikipedia.org/wiki/Televisionhttp://en.wikipedia.org/wiki/Mobile_phonehttp://en.wikipedia.org/wiki/Distortionhttp://en.wikipedia.org/wiki/Linear


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In electronics, the Darlington transistor (often called a Darlington pair) is a compound structure

consisting of two bipolar transistors (either integrated or separated devices) connected in such

a way that the current amplified by the first transistor is amplified further by the second one[1]

.

This configuration gives a much higher current gain (written , hfe, or hFE) than each transistor

taken separately and, in the case of integrated devices, can take less space than two individual

transistors because they can use a shared collector. Integrated Darlington pairs come packaged

in transistor-like integrated circuit packages.The Darlington configuration was invented by Bell

Laboratories engineer Sidney Darlington in 1953. He patented the idea of having two or three

transistors on a single chip (and sharing a single collector), but not that of an arbitrary number.

A similar configuration but with transistors of opposite type (NPN and PNP) is the Sziklai pair,

sometimes called the "complementary Darlington

TRANSISTOR-2N2222
http://en.wikipedia.org/wiki/Electronicshttp://en.wikipedia.org/wiki/Bipolar_transistorhttp://en.wikipedia.org/wiki/Darlington_transistor#cite_note-TAoE-0http://en.wikipedia.org/wiki/Darlington_transistor#cite_note-TAoE-0http://en.wikipedia.org/wiki/Electric_currenthttp://en.wikipedia.org/wiki/Gainhttp://en.wikipedia.org/wiki/Integrated_circuithttp://en.wikipedia.org/wiki/Bell_Laboratorieshttp://en.wikipedia.org/wiki/Bell_Laboratorieshttp://en.wikipedia.org/wiki/Sidney_Darlingtonhttp://en.wikipedia.org/wiki/Patenthttp://en.wikipedia.org/wiki/Sziklai_pairhttp://upload.wikimedia.org/wikipedia/commons/4/40/Darlington_configuration.svghttp://upload.wikimedia.org/wikipedia/commons/4/40/Darlington_configuration.svghttp://en.wikipedia.org/wiki/Sziklai_pairhttp://en.wikipedia.org/wiki/Patenthttp://en.wikipedia.org/wiki/Sidney_Darlingtonhttp://en.wikipedia.org/wiki/Bell_Laboratorieshttp://en.wikipedia.org/wiki/Bell_Laboratorieshttp://en.wikipedia.org/wiki/Integrated_circuithttp://en.wikipedia.org/wiki/Gainhttp://en.wikipedia.org/wiki/Electric_currenthttp://en.wikipedia.org/wiki/Darlington_transistor#cite_note-TAoE-0http://en.wikipedia.org/wiki/Bipolar_transistorhttp://en.wikipedia.org/wiki/Electronics


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The 2N2222, often referred to as the 'quad two' transistor, is a small, common NPN BJT

transistor used for general purpose low-power amplifying or switching applications. It is

designed for low to medium current, low power, medium voltage, and can operate at

moderately high speeds. It was originally made in the TO-18 metal can as shown in the picture,

but is more commonly available now in the cheaper TO-92 packaging, where it is known as the

PN2222 or P2N2222.

FEATURES

High current (max. 800 mA).

Low voltage (max. 40 V).

PINNING

APPLICATIONS

Linear amplification and switching.
http://en.wikipedia.org/wiki/NPN_transistorhttp://en.wikipedia.org/wiki/Bipolar_Junction_Transistorhttp://en.wikipedia.org/wiki/Transistorhttp://en.wikipedia.org/wiki/Amplifierhttp://en.wikipedia.org/wiki/Electric_currenthttp://en.wikipedia.org/wiki/Electric_powerhttp://en.wikipedia.org/wiki/Voltagehttp://en.wikipedia.org/wiki/TO-92http://en.wikipedia.org/wiki/TO-92http://en.wikipedia.org/wiki/Voltagehttp://en.wikipedia.org/wiki/Electric_powerhttp://en.wikipedia.org/wiki/Electric_currenthttp://en.wikipedia.org/wiki/Amplifierhttp://en.wikipedia.org/wiki/Transistorhttp://en.wikipedia.org/wiki/Bipolar_Junction_Transistorhttp://en.wikipedia.org/wiki/NPN_transistor


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MICROCONTROLLER

Introduction

FIG 1.PIC16F877 A PINOUT

To perform the various operations and conversions required to switch, control and monitor the

devices a processor is needed. The processor may be a microprocessor, micro controller or

embedded controller. In this project an micro controller has been preferred because we require

to generate clock pulse. We have chose PIC16F877A in this project mainly for the following

features.

High-Performance, Enhanced PIC Flash Microcontroller in 40-pin

The PIC16F877A CMOS FLASH-based 8-bit microcontroller is upward compatible with the

PIC16C5x, PIC12Cxxx and PIC16C7x devices. It features 200 ns instruction execution, 256 bytes

of EEPROM data memory, self programming, an ICD, 2 Comparators, 8 channels of 10-bit

Analog-to-Digital (A/D) converter, 2 capture/compare/PWM functions, a synchronous serial


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port that can be configured as either 3-wire SPI or 2-wire I2C bus, a USART, and a Parallel Slave

Port.

MEMORY ORGANIZATION

There are three memory blocks in each of the PIC16F877A devices. The program memory and

data memory have separate buses so that concurrent access can occur and is detailed in this

section.

Program Memory Organization

The PIC16F877A devices have a 13-bit program counter capable of addressing an 8K word x 14

bit program memory space. The PIC16F877A devices have 8K words x 14 bits of Flash program

memory. Accessing a location above the physically implemented address will cause a

wraparound. The Reset vector is at 0000h and the interrupt vector is at 0004h.


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DATA EEPROM AND FLASH PROGRAM MEMORY

The data EEPROM and Flash program memory is readable and writable during normal operation

(over the full VDD range). This memory is not directly mapped in the register file space. Instead,

it is indirectly addressed through the Special Function Registers. There are six SFRs used to read

and write this memory:

EECON1

EECON2

EEDATA

EEDATH

EEADR

EEADRH

When interfacing to the data memory block, EEDATA holds the 8-bit data for read/write and

EEADR holds the address of the EEPROM location being accessed. devices have 128 or 256

bytes of data EEPROM (depending on the device), with an address range from 00h to FFh. On

devices with 128 bytes, addresses from80h to FFh are unimplemented and will wraparound to

the beginning of data EEPROM memory. When writing to unimplemented locations, the on-chip

charge pump will be turned off. When interfacing the program memory block, the EEDATA and

EEDATH registers form a two-byte word that holds the 14-bit data for read/write and the

EEADR and EEADRH registers form a two-byte word that holds the 13-bit address of the

program memory location being accessed. These devices have 4 or 8K words of program Flash,

with an address range from 0000h to 0FFFh for the PIC16F874A and 0000h to 1FFFh for the

PIC16F877A. Addresses above the range of the respective device will wraparound to the

nbeginning of program memory. The EEPROM data memory allows single-byte read and write.

T0 the Flash program memory allows single-word reads and four-word block writes. Program

memory write operations automatically perform an erase-before write on blocks of four words.

A byte write in data EEPROM memory automatically erases the location and writes the new

data (erase-before-write). The write time is controlled by an on-chip timer. The write/erase

voltages are generated by an on-chip charge pump, rated to operate over the voltage range of


34/43

the device for byte or word operations. When the device is code-protected, the CPU may

continue to read and write the data EEPROM memory. Depending on the settings of the write-

protect bits, the device may or may not be able to write certain blocks of the program memory;

however, reads of the program memory are allowed. When code-protected, the device

programmer can no longer access data or program memory; this does NOT inhibit internal

reads or writes.

Architecture:

Two types of Architecture are followed.

I). Van-Neumann Architecture:

The width of addr

ess and data bus is same.

II). Haward Architecture:

The bus width of address and data may not be same. Pipelining is possible

here.

Micro controllers have built-in peripherals, they are:

1. Memory

a. Program Memory (E.g. PROM, Flash memory)

b. Data Memory (E.g. RAM, EEROM)

2. I/O Ports

3. ADC

4. Timers

5. USART

6. Interrupt Controllers

7. PWM / Capture


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PERIPHERALS OF PIC16F877A

As the PIC16F877A is rich in peripherals so you can use it for many different projects

PM DM

I / O

CPU Ports

Timer /

Counter PWM/

Port A

Port B

Port C

Port D

Port E


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PERIPHERALS OF PIC16F877A


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FEATURES OF PIC16F877A

High-Performance RISC CPU

Lead-free; RoHS-compliant

Operating speed: 20 MHz, 200 ns instruction cycle

Operating voltage: 4.0-5.5V

Industrial temperature range (-40 to +85C)

15 Interrupt Sources

35 single-word instructions

All single-cycle instructions except for program branches (two-cycle)

Special Microcontroller Features

Flash Memory: 14.3 Kbytes (8192 words)

Data SRAM: 368 bytes

Data EEPROM: 256 bytes

Self-reprogrammable under software control

In-Circuit Serial Programming via two pins (5V)

Watchdog Timer with on-chip RC oscillator

Programmable code protection

Power-saving Sleep mode

Selectable oscillator options

In-Circuit Debug via two pins

Peripheral Features

33 I/O pins; 5 I/O ports

Timer0: 8-bit timer/counter with 8-bit prescaler

Timer1: 16-bit timer/counter with prescaler

o Can be incremented during Sleep via external crystal/clock


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Timer2: 8-bit timer/counter with 8-bit period register, prescaler and postscaler

Two Capture, Compare, PWM modules

o 16-bit Capture input; max resolution 12.5 ns

o 16-bit Compare; max resolution 200 ns

o 10-bit PWM

Synchronous Serial Port with two modes:

o SPI Master

o I2C Master and Slave

USART/SCI with 9-bit address detection

Parallel Slave Port (PSP)

o 8 bits wide with external RD, WR and CS controls

Brown-out detection circuitry for Brown-Out Reset

Analog Features

10-bit, 8-channel A/D Converter

Brown-Out Reset

Analog Comparator module

o

analog comparators

o Programmable on-chip voltage reference module

o Programmable input multiplexing from device inputs and internal VREF

o Comparator outputs are externally accessible

ADVANTAGES

The 16F877A is one of the most popular PIC microcontrollers and it's easy to see why - it comes

in a 40 pin DIP pinout and it has many internal peripherals. The 40 pins make it easier to use

the peripherals as the functions are spread out over the pins. This makes it easier to decide

what external devices to attach without worrying too much if there enough pins to do the job.


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One of the main advantages is that each pin is only shared between two or three functions so

its easier to decide what the pin function (other devices have up to 5 functions for a pin).

DISADVANTAGE

A disadvantage of the device is that it has no internal oscillator so you will need an externalcrystal of other clock source.

DIODE RECTIFIER-IN4007

The diodes are used to convert AC into DC these are used as half wave rectifier or full wave

rectifier. Three points must he kept in mind while using any type of diode.

Maximum forward current capacity

Maximum reverse voltage capacity

Maximum forward voltage capacity

GENERAL DESCRIPTION

In this project the diode rectifier is used in the main circuit. Usually all the power electronics

circuits are provided with a diode rectifier. This helps to convert the 12V AC voltage to DC

voltage. They are connected at the output of input filters.

FEATURES

Diffused Junction

High Current Capability

Low Forward Voltage Drop

Surge Overload Rating to 30A Peak

Low Reverse Leakage Current

Plastic Material: UL Flammability

Classification Rating 94V-0


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MECHANICAL DATA

Case: Molded Plastic

Terminals: Plated Leads Solderable per

MIL-STD-202, Method 208

Polarity: Cathode Band

Weight: DO-41 0.30 grams (approx) A-405 0.20 grams (approx)

Mounting Position: Any

Marking: Type Number

MOSFET SWITCH-IRFP250N

Definition of MOSFET

(Metal Oxide Semiconductor Field Effect Transistor). The most popular and widely used type of

field effect transistor (see FET). MOSFETs are either NMOS (n-channel) or PMOS (p-channel)

transistors, which are fabricated as individually packaged discrete components for high power

applications as well as by the hundreds of millions inside a single chip (IC).
http://www.pcmag.com/encyclopedia_term/0,2542,t=FET&i=43105,00.asphttp://www.pcmag.com/encyclopedia_term/0,2542,t=FET&i=43105,00.asp


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GENERAL DESCRIPTION

In our project the MOSFET switch is connected to the main circuit.Here we have two switches

namely

Main switch Sm

Auxiliary switch Sa

The pulse to these switches is given using micro controller PIC16F877A through a driver

circuit. In PIC16F877A the pulse of 5V is generated which is sent to driver circuit, these

signal is amplified to about 12V DC, that is sent to the MOSFET switch Sm and Sarespectively.

USING MOSFET AS A SWITCH

A field effect transistor operates in a very similar way to the transistor that we have just

experimented with except that the main current flow is controlled by an electrostatic field. An

FET has the great advantage that no current flows into the control input (called the gate), the

main current is turned on and off by the level of voltage on the gate.

FETs are available in many different types and with various drive level requirements. We are


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going to keep it simple and not get into these complications. The MOSFET that we will be using

is a logic level MOSFET - they are designed to be driven directly from the output lines of

microcontrollers that is all we need to know!For these experiments we will be using the BS270

N channel MOSFET. As it is designed for logic level inputs we know that when the gate is

connected to ground it is turned off and when the gate is connected to 5 volts it is turned on.

We do not need to use a resistor between the push button switch and the gate because the

current is very very low whatever the input voltage (if kept within 0 to 5 volts).

The MO and the FE

The "metal oxide" in MOS comes from the first devices that used a metal gate over oxide

(silicon dioxide). Subsequently, poly-crystalline silicon was used for the gate, but MOS was

never renamed. The "field-effect" in FET is the electromagnetic field that is generated when the

gate electrode is energized, causing the transistor to turn on or off.

NMOS and PMOS

In NMOS transistors, the silicon channel between the source and drain is of p-type silicon.

When a positive voltage is placed on the gate electrode, it repulses the holes in the p-type

material forming a conducting (pseudo n-type) channel and turning the transistor on. Anegative voltage turns the transistor off. With a PMOS transistor, the opposite occurs. A

positive voltage on the gate turns the transistor off, and a negative voltage turns it on. NMOS

transistors switch faster than PMOS.

CMOS

When an NMOS and PMOS transistor are wired together in a complementary fashion, they

become a CMOS (complementary MOS) gate, which causes no power to be used until thetransistors switch. CMOS is the most widely used microelectronic design process and is found in

almost every electronic product. See n-type silicon, bipolar transistor, chip and FET.
http://www.pcmag.com/encyclopedia_term/0,2542,t=n-type+silicon&i=47578,00.asphttp://www.pcmag.com/encyclopedia_term/0,2542,t=bipolar+transistor&i=59377,00.asphttp://www.pcmag.com/encyclopedia_term/0,2542,t=chip&i=39636,00.asphttp://www.pcmag.com/encyclopedia_term/0,2542,t=FET&i=43105,00.asphttp://www.pcmag.com/encyclopedia_term/0,2542,t=FET&i=43105,00.asphttp://www.pcmag.com/encyclopedia_term/0,2542,t=chip&i=39636,00.asphttp://www.pcmag.com/encyclopedia_term/0,2542,t=bipolar+transistor&i=59377,00.asphttp://www.pcmag.com/encyclopedia_term/0,2542,t=n-type+silicon&i=47578,00.asp


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INDUCTORS:

An inductor or reactor is a passive electrical component that can store energy in a magnetic

field created by the electric current passing through it. An inductor's ability to store magnetic

energy is measured by its inductance, in units ofhenries. Typically an inductor is a conducting

wire shaped as a coil, the loops help create a strong magnetic field inside the coil due to

Faraday's law of induction. Inductors are one of the basic electronic components used in

electronics where current and voltage change with time, due to the ability of inductors to delay

and reshape alternating currents.An "ideal inductor" has inductance, but no resistance or

capacitance, and does not dissipate energy. A real inductor is equivalent to a combination of

inductance, some resistance due to the resistivity of the wire, and some capacitance. At some

frequency, usually much higher than the working frequency, a real inductor behaves as a

resonant circuit (due to its self capacitance). In addition to dissipating energy in the resistance

of the wire, magnetic core inductors may dissipate energy in the core due to hysteresis, and at

high currents may show other departures from ideal behavior due to nonlinearity.

CONCLUSIONS:

Solar (PV) power system has a great potential in future as one of renewable energy

technologies for off-grid power generation. The hybrid technology, integrating PV with DG,

offers solution to off-grid power generation. The easy installation and maintenance free

operational feature of the hybrid system created more popularity among the rural masses.
http://en.wikipedia.org/wiki/Passive_componenthttp://en.wikipedia.org/wiki/Electronic_componenthttp://en.wikipedia.org/wiki/Energyhttp://en.wikipedia.org/wiki/Magnetic_fieldhttp://en.wikipedia.org/wiki/Magnetic_fieldhttp://en.wikipedia.org/wiki/Electric_currenthttp://en.wikipedia.org/wiki/Inductancehttp://en.wikipedia.org/wiki/Henry_(unit)http://en.wikipedia.org/wiki/Faraday%27s_law_of_inductionhttp://en.wikipedia.org/wiki/Electrical_resistancehttp://en.wikipedia.org/wiki/Capacitancehttp://en.wikipedia.org/wiki/Resonant_circuithttp://en.wikipedia.org/wiki/Parasitic_capacitancehttp://en.wikipedia.org/wiki/Hysteresishttp://en.wikipedia.org/wiki/Linear_circuithttp://en.wikipedia.org/wiki/Linear_circuithttp://en.wikipedia.org/wiki/Hysteresishttp://en.wikipedia.org/wiki/Parasitic_capacitancehttp://en.wikipedia.org/wiki/Resonant_circuithttp://en.wikipedia.org/wiki/Capacitancehttp://en.wikipedia.org/wiki/Electrical_resistancehttp://en.wikipedia.org/wiki/Faraday%27s_law_of_inductionhttp://en.wikipedia.org/wiki/Henry_(unit)http://en.wikipedia.org/wiki/Inductancehttp://en.wikipedia.org/wiki/Electric_currenthttp://en.wikipedia.org/wiki/Magnetic_fieldhttp://en.wikipedia.org/wiki/Magnetic_fieldhttp://en.wikipedia.org/wiki/Energyhttp://en.wikipedia.org/wiki/Electronic_componenthttp://en.wikipedia.org/wiki/Passive_component

Design of Solar Power System for Home Application

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