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CHAPTER 1

INTRODUCTION

1.1 INTRODUCTION TO SOLAR ENERGY

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 650,000,0001tons 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.

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

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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.

1.2 USES OF SOLAR ENERGY

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.

1.2.1 HEATING

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

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.

FIG 1.1 – HEATING APPLICATION OF SOLAR ENERGY

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1.2.2 COOLING

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.

FIG 1.2 – COOLING THROUGH SOLAR CELL

1.2.3 TRANSPORTATION

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

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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.

1.2.4 GENERATION OF ELECTRICITY

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.

FIG 1.3 – GENERATION OF ELECTRICITY FROM SOLAR ENERGY

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

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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.

Now, we know that solar panel transfers electrons into DC, and most appliance at home is using

AC, that's why we use inverters.

1.3 BASIC PRINCIPLE OF SOLAR INVERTER

A solar inverter, or PV inverter, converts the variable direct current (DC) output of a

photovoltaic (PV) solar panel into a utility frequency alternating current (AC) that can be fed

into a commercial electrical grid or used by a local, off-grid electrical network. It is a critical

component in a photovoltaic system, allowing the use of ordinary commercial appliances. Solar

inverters have special functions adapted for use with photovoltaic arrays, including maximum

power point tracking and anti-islanding protection

1.4 NEED OF SOLAR INVERTER

There are two types of sources for electrical power generation. One is conventional and other

is non- conventional. Today to generate most of electrical power conventional sources like coal,

gas, nuclear power generators are used. Some of conventional source are polluted the

environment to generate the electricity. And nuclear energy is not much preferable because of

its harmful radiation effect on the mankind. After some of ten years conventional sources will

not sufficient enough to fulfill the requirements of the mankind. So some of the electrical power

should be generated by non-conventional energy sources like solar, wind .With the

continuously reducing the cost of PV power generation and the further intensification of energy

crisis, PV power generation technology obtains more and more application.

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Conventionally, there are two ways in which electrical power is transmitted. Direct current

(DC) comes from a source of constant voltage and is suited to short-range or device level

transmission. Alternating current (AC) power consists of a sinusoidal voltage source in which

a continuously changing voltage (and current) can be used to employ magnetic components.

Long distance electrical transmission favors AC power, since the voltage can be boosted easily

with the use of transformers. By boosting the voltage, less current is needed to deliver a given

amount of power to a load, reducing the resistive loss through conductors.

The adoption of AC power has created a trend where most devices adapt AC power from an

outlet into DC power for use by the device. However, AC power is not always available and

the need for mobility and simplicity has given batteries an advantage in portable power. Thus,

for portable AC power, inverters are needed. Inverters take a DC voltage from a battery or a

solar panel as input, and convert it into an AC voltage output.

FIG 1.4 – SOLAR INVERTER SCHEMATICS

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1.5 TYPES OF SOLAR INVERTER

Solar inverters may be classified into three broad types.

1. Stand Alone Inverters

2. Grid Tie Inverters

3. Battery Backup Inverters

1.5.1 STAND ALONE INVERTERS

Stand-alone inverters, used in isolated systems where the inverter draws its DC energy from

batteries charged by photovoltaic arrays. Many stand-alone inverters also incorporate

integral battery chargers to replenish the battery from an AC source, when available. Normally

these do not interface in any way with the utility grid, and as such, are not required to have anti-

islanding protection.

1.5.2 GRID TIE INVERTERS

Grid-tie inverters, which match phase with a utility-supplied sine wave. Grid-tie inverters are

designed to shut down automatically upon loss of utility supply, for safety reasons. They do not

provide backup power during utility outages.

1.5.3 BATTERY BACKUP INVERTERS

Battery backup inverters, are special inverters which are designed to draw energy from a

battery, manage the battery charge via an onboard charger, and export excess energy to the

utility grid. These inverters are capable of supplying AC energy to selected loads during a utility

outage, and are required to have anti-islanding protection.

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CHAPTER 2

LITERATURE SURVEY

2.1 ENERGY SOURCES

An energy resource is something that can produce heat, power life, move objects, or produce

electricity. Matter that stores energy is called a fuel. Human energy consumption has grown

steadily throughout human history.

There are two type of energy sources

1) Non Renewable Energy Sources

2) Renewable Energy Sources

2.1.1 NON RENEWABLE ENERGY SOURCES

Non-renewable energy comes from sources that will run out or will not be replenished in our

lifetimes—or even in many, many lifetimes. Most non-renewable energy sources are fossil

fuels: coal, petroleum, and natural gas. Carbon is the main element in fossil fuels.

2.1.2 RENEWABLE ENERGY SOURCES

Wind, solar, and biomass are three emerging renewable sources of energy. Renewable energy

is generally defined as energy that is collected from resources which are naturally replenished

on a human timescale, such as sunlight, wind, rain, tides, waves, and geothermal heat.

2.2 SOLAR ENERGY AS 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.

2.2.1 POLLUTION FREE ENERGY

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

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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

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.

2.2.2 REDUCTION IN GREEN HOUSE GASES

Global warming and energy policies have become a hot topic on the international agenda in the

last years. Developed countries are trying to reduce their greenhouse gas emissions. For

example, the European Union has committed to reduce their greenhouse gas to at least 20%

below 1990 levels and to produce no less than 20% of its energy consumption from renewable

sources by 2020. In this context, photovoltaic (PV) power generation has an important role to

play due to the fact that it is a green source. The only emissions associated with PV power

generation are those from the production of its components. After their installation they

generate electricity from the solar irradiation without emitting greenhouse gases. In their life

time, PV panels produce more energy than that for their manufacturing. Also, they can be

installed in places with no other use, such as roofs and deserts.

2.2.3 ENERGY PRODUCTION ON REMOTE LOCATIONS

They can produce electricity for remote locations, where there is no electricity network. The l

atter type of installations is known as off-grid facilities and sometimes they are the most econ

omical alternative to provide electricity in isolated areas. However, most of the PV power gen

eration comes from grid-connected installations, where the power is fed in the electricity netw

ork. In fact, it is a growing business in developed countries such as Germany which is world l

eader in PV power generation followed by Spain, Japan, USA and Italy.

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.

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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.

FIG 2.1 – ELECTRICTY GENERATION FROM REMOTE LOCATIONS

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 person 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

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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.

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.

FIG 2.2 – ROLE OF SOLAR ENERGY IN RENEWABLE ENERGY CONSUMPTION

2.3 BACKGROUND STUDY

The use of efficient photovoltaic solar cells has emerged as an important solution in energy

conservation and demand side management. Owing to their initial high costs, they have not

been an attractive alternative for users who are able to buy cheaper electrical energy from the

utility grid. However, they have been extensively used in pumping and air conditioning in

remote and isolated areas where utility power is not available or too expensive to transport.

Although solar cell prices have decreased considerably during the last years due to new

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developments in the film technology and the manufacturing process, PV arrays are still

considered rather expensive compared with the utility fossil fuel generated electricity prices.

After building such an expensive renewable energy system, the PV array has to be operated at

its highest conversion efficiency by continuously utilizing the maximum available output of

the array. The electrical system powered by solar cells requires special design considerations

because of the varying nature of the solar power generated resulting from unpredictable

changes in weather conditions which affect the solar radiation level as well as the cell operating

temperature.

The efficiency of a PV plant is affected mainly by three factors: the efficiency of the PV panel

(in commercial PV panels it is between 8-15%). The efficiency of the inverter (95-98%) and

the efficiency of the maximum power point tracking algorithm (which is over 98%). Improving

the efficiency of the PV panel and that of the inverter is not easy as it depends on the technology

available. It may require better components, which can increase drastically the cost of the

installation. Instead, improving the tracking of the maximum power point with new control

algorithms is easier, not expensive and can be done even in plants which are already in use by

updating their control algorithms, which would lead to an immediate increase in PV power

generation and consequently a reduction in its price.

In practice, the voltage dependency on the irradiation is often neglected. As the effect on both

the current and voltage is positive, i.e. both increase when the irradiation rises, the effect on

the power is also positive. More the irradiation, the more power is generated. PV panel

manufacturers provide in their data sheets the temperature coefficients, which are the

parameters that specify how the open circuit voltage, the short circuit current and the maximum

power vary when the temperature changes. As the effect of the temperature on the current is

really small, it is usually neglected.

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2.4 PROBLEM STATEMENT

The world demand for electric energy is constantly increasing, and conventional energy

resources are diminishing and are even threatened to be depleted. Moreover; their prices are

rising. For these reasons, the need for alternative energy sources has become indispensable,

and solar energy in particular has proved to be a very promising alternative because of its

availability and pollution-free nature. Due to the increasing efficiencies and decreasing cost of

photovoltaic cells and the improvement of the switching technology used for power conversion,

our goal is to design an inverter powered by PV panels and that could supply stand-alone AC

loads.

Solar panels produce direct currents (DC), and to connect these panels to the electricity grid or

use them in other industrial applications, we should have an AC output at a certain required

voltage level and frequency. The conversion from DC to AC is essentially accomplished by

means of a DC-AC inverter, which is the major component in the system. Yet, the output of

the solar panels is not continuously constant and is related to the instantaneous sunlight

intensity and ambient temperature.

2.5 OBJECTIVE AND SCOPE

The main objective of our project is to design and construct a PV based system that produces

electric energy and operates in dual mode, supplying stand-alone AC loads, while minimizing

its cost and size.

The system’s main property is to production of quality electricity from a renewable source to

reduce dependence on fossil fuels and the associated emissions of pollutants.

Our goal is to design and develop an inverter that will handle the task described.

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2.6 RESEARCH

2.6.1 SOURCE OF INFORMATION

The development of renewable energy such as sun, geothermal, biomass and wind have become

important contribution to the total energy consumed in the world. These alternative sources of

energy can never be exhausted. They cause less emission and therefore stand out as a

potentially feasible source of clean and limitless energy. These resources do not cause any

significant environmental pollution or substantial health hazards and apparently available as

natural abundant resources. Solar energy is amongst the highest development of renewable

resources. Malaysia is one of the countries that receive abundant of sun light in average mostly

in northern side of Peninsular Malaysia. Perlis, Kedah and Penang have high potential in

applying solar energy. With the rapid progress of the power electronic techniques, solar energy

as an alternative energy source has been put to use such as photovoltaic (PV) module. The basic

concept for PV module is to collect solar energy in space and transfer it for distribution as

electrical power. However this renewable source energy requires rather sophisticated

conversion techniques to make them usable to the end user. The output of PV is essentially

direct current (DC) form. Therefore, it needs to be converted to alternating current (AC) for it

to be commercially feasible. This is necessary because the power utilization is mostly in AC

form. This conversion can be done by using inverter. In any PV based system, the inverter is a

critical component responsible for the control of electricity flow between the modules, battery

and loads. Inverters are essentially DC-AC converters. It converts DC input into AC output. It

can be designed to be used with different voltage ranges and topologies for varying applications

A solar inverter takes the DC electricity from the solar array and uses that to create AC

electricity. Inverters are like the brains of the system. Along with inverting DC to AC power,

they also provide ground fault protection and system stats including voltage and current on AC

and DC circuits, energy production, and maximum power point tracking.

When sufficient output available from Solar panels to charge the battery, solar panel charges a

storage battery. In this time mains supply will not be utilized for charging purpose. A control

circuit continuously monitors the battery's voltage. When the battery is fully charged, the circuit

automatically turns on a power inverter and switches the appliance from running on grid power

to running on the energy stored in the battery. Then when the battery's voltage drops too low,

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the circuit automatically switches the appliance back to grid power until the battery is

recharged.

we can run the equipment like fans, LED lights, pumps etc. directly without using battery, but

as the output of Solar panels are not steady due to clouds, bad weather etc. It’s not advisable to

run the appliances which require stable voltage. However with suitable regulators, you can very

easily run low power devices. Solar pumps works directly on the direct input from Solar panels.

Solar pump is a combination of a DC motor and a centrifugal pump. Solar submersible pump

sets are also available. Solar pump sets are extremely useful where Grid power supply is not

accessible. In India a typical 1 HP, 500 W input 24 volt solar pump set costs 35000/- to 40000/-

without the cost of Solar panel and fittings. A complete set can cost around Rs 1 Lakh. These

pump set can deliver around 1500 liters of water per hour on sunny days.

There are few sections of the solar inverter they are:

1) The solar battery recharger,

2) The solar panel

3) Rechargeable battery

4) The inverter.

2.6.2 REQUIRED INPUT DATA

Solar PV system includes different components that should be selected according to your

system type, site location and applications. The major components for solar PV system are

solar charge controller, inverter, battery bank, auxiliary energy sources and loads (appliances).

1) Size and Rating of Solar Panel – converts sunlight into DC electricity.

2) Solar charge controller – regulates the voltage and current coming from the PV panels

going to battery and prevents battery overcharging and prolongs the battery life.

3) Size of Inverter – converts DC output of PV panels or wind turbine into a clean AC

current for AC appliances or fed back into grid line.

4) Size of Battery Bank – stores energy for supplying to electrical appliances when there

is a demand.

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5) Load – is electrical appliances that connected to solar PV system such as lights, radio,

TV, computer, refrigerator, etc.

6) Type of Connection of Solar Panel

7) Energy from Solar Panel as per Daily Sun lights

8) Select Type of connection of Batteries in Battery Bank

2.7 DESIGN APPROACHES OF SOALR INVERTER

There are many topologies or circuit designs for creating higher power AC from low voltage

DC sources. Two common topologies are the Push-Pull and H-Bridge. The Push-Pull topology

is suitable for producing square and modified square wave inverter while the H-Bridge is useful

for producing modified square wave and sine wave inverter.

FIG 2.3 – GENERAL FLOW OF AN INVERTER

2.7.1 PUSH PULL TOPOLOGY

The basic theory of Push-Pull topology is shown in Fig 2.4. There are two transistor switches

in this design. If the top switch closes, it will cause current to flow from the battery negative

through the transformer primary to the battery positive. This induces a voltage in the secondary

side of the transformer that is equal to the battery voltage times the turn’s ratio of the

transformer.

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FIG 2.4 – PUSH-PULL TOPOLOGY FOR SQUARE WAVE OUTPUT

This phenomena flow is shown in Fig 2.5(a). Only one switch is closed at a time. The switches

flip-flop after a period of approximately 8ms which is one-half of 60Hz AC cycle. The top

switch opens and then the bottom switch closes allowing current to flow in the opposite

direction as illustrate in Fig. 2.5(b). The continuing of closes and opens switch will produce a

square wave output waveform which is higher voltage AC power.

FIG 2.5 – (A) TOP SWITCH CLOSING STATE (B) BOTTOM SWITCH CLOSE STATE

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The addition of an extra winding in the transformer along with a few other parts allows output

of a Modified Square Wave.

2.7.2 H- BRIDGE TOPOLOGY

The operation of H-Bridge topology is similar to Push-Pull topology. The term H-Bridge is

derived from the typical graphical representation of such a circuit. An H-Bridge is built with

four transistor switches. The transistors are divided into four groups with the transformer

primary connected across the middle of the bridge as illustrate in Fig 2.6.

FIG 2.6– H BRIDGE TOPOLOGY

The transistors are switched on and off in a specific pattern to produce each part of the

waveform. If the switch 1 and 4 are closed, current will flow from the battery negative through

transformer primary to the positive terminal of the battery as shown in Fig. 9(a). This current

induces a current flow in the secondary of the transformer, which has a peak voltage equal to

the battery voltage times the turn ratio of the transformer. The switch 1 and 4 open after a

period of time and the switch 2 and 4 close providing off time shorting like in Fig. 9(b). The

length of the on and off time is determined according to the Pulse Width Modulation (PWM)

controller.

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Then, the switch 2 and 3 are close and allow current flow through the transformer in a direction

opposite to the current flow. The switch 2 and 4 are close after this cycle is complete for off

time shorting. This cycle will continuous to produce AC power.

2.8 SOLAR INVERTER PARTS

There are few sections of the solar inverter they are:

1. The solar battery recharger,

2. The solar panel

3. Rechargeable battery

4. The inverter.

2.8.1 SOLAR BATTERY CHARGER

A battery charger is a device used to put energy into a secondary cell or (rechargeable) batter

y by forcing an electric current through it. The charge current depends upon the technology an

d capacity of the battery being charged. For example, the current that should be applied to rec

harge a 12 V car battery will be very different from the current for a mobile phone battery

The solar battery recharger as the name suggest it is in fact a battery charger which charges a s

ealed rechargeable battery of 6V 4.5 AH in this case. The solar battery charger derives its pow

er from the12V 500mA solar panel. The solar panel which in turn converts the sunlight to ele

ctrical energy. The charger converts the raw 12V from the solar panel to a regulated voltage f

eed for the sealed rechargeable battery.

The solar battery recharger features:

1. Custom controllable voltage regulation.

2. Auto cut-off when battery is fully charged.

3. Filtered input from the solar panel.

4. No current back flows from the battery.

5. Very simple, compact and efficient.

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2.8.2 SOLAR PANEL

A solar panel (also solar module, photovoltaic module or photovoltaic panel) is a packaged,

connected assembly of solar cells, also known as photovoltaic cells. The solar panel can be

used as a component of a larger photovoltaic system to generate and supply electricity in

commercial and residential applications.

Because a single solar panel can produce only a limited amount of power, many installations

contain several panels. A photovoltaic system typically includes an array of solar panels, an

inverter, and sometimes a battery and interconnection wiring.

FIG 2.7 – SOLAR PANEL

Solar panels use light energy (photons) from the sun to generate electricity through the

photovoltaic effect. The structural (load carrying) member of a module can either be the top

layer or the back layer. The majority of modules use wafer- based crystalline silicon cells or

thin-film cells based on cadmium telluride or silicon. The conducting wires that take the current

off the panels may contain silver, copper or other non-magnetic conductive transition metals.

The cells must be connected electrically to one another and to the rest of the system. Cells must

also be protected from mechanical damage and moisture. Most solar panels are rigid, but semi-

flexible ones are available, based on thin-film cells.

Electrical connections are made in series to achieve a desired output voltage and/or in parallel

to provide a desired current capability. Separate diodes may be needed to avoid reverse

currents, in case of partial or total shading, and at night. The p-n junctions of mono-crystalline

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silicon cells may have adequate reverse current characteristics that these are not necessary.

Reverse currents waste power and can also lead to overheating of shaded cells. Solar cells

become less efficient at higher temperatures and installers try to provide good ventilation

behind solar panels.

Some recent solar panel designs include concentrators in which light is focused by lenses or

mirrors onto an array of smaller cells. This enables the use of cells with a high cost per unit

area (such as gallium arsenide) in a cost-effective way.

Depending on construction, photovoltaic panels can produce electricity from a range of

frequencies of light, but usually cannot cover the entire solar range (specifically, ultraviolet,

infrared and low or diffused light). Hence much of the incident sunlight energy is wasted by

solar panels, and they can give far higher efficiencies if illuminated with monochromatic light.

Therefore, another design concept is to split the light into different wavelength ranges

and direct the beams onto different cells tuned to those ranges. This has been projected to be

capable of raising efficiency by 50%.

Currently the best achieved sunlight conversion rate (solar panel efficiency) is around 21% in

commercial products, typically lower than the efficiencies of their cells in isolation. The energy

density of a solar panel is the efficiency described in terms of peak power output per unit of

surface area, commonly expressed in units of watts per square foot (W/ft2). The most efficient

mass-produced solar panels have energy density values of greater than 13 W/ft2 (140 W/m2).

2.8.3 RECHARGABLE BATTERY

The battery used in this project is a rechargeable sealed lead sulphate battery rating 12V 4.5AH.

This type of battery is excellent for rechargeable purpose

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

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network. Several different combinations of chemicals are commonly used, including: lead–

acid, nickel cadmium (NiCd), nickel metal hydride (NiMH),lithium ion (Li-ion), and lithium

ion polymer (Li-ion polymer).

FIG 2.8 – RECHARGABLE BATTERY

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.

2.8.4 INVERTER

Since normal dc can’t be used in most applications due to which there is a requirement that

somehow the dc is changed to ac for this the inverter is used which converts the dc to ac of

suitable range for use in house hold appliances.

In this project the dc from the sealed rechargeable battery of 6V is fed to the inverter which

then converts it to ac of 140V – 220V this makes it possible to recharge normal mobile chargers.

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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. The inverter performs the opposite

function of a rectifier.

2.9 MODELLING OF 50WATT SOLAR INVERTER

A successful design involves accurate knowledge of daily electrical load calculation and

accounts for all worst case scenarios which might possibly occur during operation. A good

designer will be pragmatic and keep the costs down by cutting on unnecessary over sizing the

system.

2.9.1 SELECTION OF BATTERY SIZE AND SOLAR PANEL

Now let’s begin,

Suppose we have to design an inverter for load of 40 Watts and required backup time for

batteries is 1 Hour and we have to model a Solar Inverter than Inverter ratings, Required No of

Solar Panel and No of batteries are calculated as follows.

Inverter should be greater 25% than the total Load

40 x (25/100) = 10

40+10 = 50 Watts

This is the rating of the UPS (Inverter)

Now the required Back up Time in Hours = 2.5 Hours

Suppose we are going to install 4.5Ah, 6 batteries,

6V x 4.5Ah = 27Wh

Now for One Battery (i.e. the Backup time of one battery)

24

27Wh / 40W = 0.675 Hours

But our required Backup time is 1 Hour.

Therefore, 1/0.675 = 2→ i.e. we will now connect two batteries each of 4.5Ah, 6V.

So this is a 12 V inverter system, now we will install two batteries (each of 6V, 4.5Ah) in

Parallel. Because this is a 6V inverter System, so if we connect these batteries in parallel, then

the Voltage of batteries 6V remains same, while it’s Ah (Ampere Hour) rating will be increase

1. In parallel Connection, Voltage will be same in each wire or section, while current will

be different i.e. current is additive e.g. I1+I2+I3…+In = 4.5Ah +4.5Ah = 9Ah

2. In Series Circuits, Current is same in each wire or section while voltage is different i.e.

Voltage is additive e.g.V1+V2+V3….Vn. For The above system if we connect these

batteries in series instead of parallel, then The rating of batteries become V1+V2 = 12V

while the current rating would be same i.e. 4.5Ah.

We will now connect 2 batteries in parallel (each of 4.5Ah, 6V), therefore for two Batteries it

will be 9 Ah 6V, Now Required Charging Current for these two batteries (Charging current

should be 1/10 of batteries Ah) → 9Ah x (1/10) = 0.9A

Now the required No of Solar Panels

P = VI

P = 6V x 0.9 A

P = 5.4 Watts

This is our required watts for solar panel (only for battery charging, and then battery will supply

power to the load), Now

5.4W/3W = 2 Solar panels

Or 5.4W/6 = 1 Solar panels

25

2.9.2 SELECTION OF TOPOLOGY

The Push-Pull topology was the first step in electronic inverter technology. The advantage of

this topology is the simplicity of the overall circuit design and cost effective in manufacturing.

But, the major problem is the current in the transformer has to suddenly reverse directions. This

will causes a large reduction in efficiency. The disadvantages of this topology are complexity

of the transformer design and higher transformer losses in square wave design.

The square wave inverter is the simplest and cheapest form of inverter. But, the output

waveform of square wave inverter has high total harmonic distortion (THD). Motor will

generate excess heat and most of electronic equipment will not operate well from square wave

inverter. Modified square wave inverters have better improvement over square wave types. It

has good voltage regulation, lower total harmonic distortion and better overall efficiency. The

operation of electric motor is better from a modified square wave and most electronic

component will operate without problems.

The advantage of H-Bridge topology is the simplicity of needing only one primary winding on

the transformer. The efficiency of this design based on the quality of the transistors used and

the number of transistors in parallel. Mostly, the losses in this topology are at the transistor

switches. The performance of this design will improve as transistors improve and become

available.

For small load applications in PV system, the inverter can be design by using the Push-Pull

topologies. This topology is simple and easy to design. This kind of inverter can run the lamp

and fan. However some modification of the design is needed for this topology. The next step

will continue with further improvement in the circuit design and simulation of this topology in

order to improve and modify the circuit design.

26

CHAPTER 3

COMPONENT REQUIRED AND DESCRIPTION

3.1 COMPONENTS REQUIRED

S. No Component Ratings

1. THE SOLAR BATTERY CHARGER

i. Step Down Transformer 230V/12V, 1A

ii. Diodes IN4001, IN 4007

iii. Capacitors 470µF, 50V

iv. Voltage regulator IC 7812 IC 7812

v. Transistor BC547

vi. Resistors (Each 0.25 watt) 10kΩ,1.5kΩ,100kΩ

vii. Buzzer 12V

2. INVERTER

i. IC CD4047 CD4047

ii. Resistors 1K, 18K, 100Ω- 0.5W

iii. Capacitor 0.22µF

iv. MOSFET IRFZ44

v. Step Down Transformer 230V/12V-0-12V,5A

3. Battery 12V,4.5Ah

4. Miscellaneous

27

3.2 COMPONENT DESCRIPTION

3.2.1 TRANSFORMER

A transformer is an electrical device and it consists of 2 coils of wire that are joined by an iron

core. It offers the much required capability of changing the current and voltage levels simply.

The main function of the transformer is that to increase (step-up) or decrease (step-down) AC

voltages. The transformer works on the principle of Faraday’s law of electromagnetic

induction, that is, mutual inductance between 2 circuits that is linked by a common magnetic

flux. Transformer converts an electrical energy from one circuit to another circuit with the

help of mutual induction between the 2 windings without electrical connection between them,

and also converts power from one circuit to another} circuit without changing the frequency

however with a different voltage level.

In a step up transformer, secondary winding contains a lot of winding than the first coil.

Returning to a transformer, it has more windings in the primary than the secondary winding.

These are one of the main reasons we use AC current in our homes and not DC. DC voltages

can’t be modified using transformers.

FIG. 3.1 220/12V TRANSFORMER

3.2.2 DIODE

The 1N4007 series (or 1N4000 series) is a family of popular 1.0 amp general purpose silicon

rectifier diodes commonly used in AC adapters for common household appliances. Blocking

28

voltage varies from 50 to 1000 volts. This diode is made in an axial-lead DO-41 plastic

package.

The 1N5400 series is a similarly popular series for higher current applications, up to 3 A. These

diodes come in the larger DO-201 axial package. These are fairly low-speed rectifier diodes,

being inefficient for square waves of more than 15 kHz. The series was second sourced by

many manufacturers. The 1N4000 series were in the Motorola Silicon Rectifier Handbook in

1966, as replacements for 1N2609 through 1N2617.

FIG. 3.2 DIODE

These devices are widely used and recommended. The table below shows the maximum

repetitive reverse blocking voltages of each of the members of the 1N4000 and 1N5400 series

3.2.3 ELECTROLYTIC CAPACITOR

A capacitor is a tool consisting of two conductive plates, each of which hosts an opposite

charge. These plates are separated by a dielectric or other form of insulator, which helps them

maintain an electric charge. There are several types of insulators used in capacitors. Examples

include ceramic, polyester, tantalum air, and polystyrene. Other common capacitor insulators

include air, paper, and plastic. Each effectively prevents the plates from touching each other.

A capacitor is often used to store analogue signals and digital data. Another type of capacitor

is used in the telecommunications equipment industry.

FIG. 3.3 IMAGE OF ELECTROLYTIC CAPACITOR

29

This type of capacitor is able to adjust the frequency and tuning of telecommunications

equipment and is often referred to a variable capacitor. A capacitor is also ideal for storing an

electron. A capacitor cannot, however, make electrons. A capacitor measures in voltage, which

differs on each of the two interior plates. Both plates of the capacitor are charged, but the

current flows in opposite directions. A capacitor contains 1.5 volts, which is the same voltage

found in a common AA battery. As voltage is used in a capacitor, one of the two plates

becomes filled with a steady flow of current. At the same time, the current flows away from

the other plate. To understand the flow of voltage in a capacitor, it is helpful to look at naturally

occurring examples. Lightning, for example, is similar to a capacitor. The cloud represents

one of the plates and the ground represents the other. The lightning is the charging factor

moving between the ground and the cloud.

3.2.4 VOLTAGE REGULATOR IC 7812

7812 is a famous IC which is being widely used in 12V voltage regulator circuits. Truly

speaking it is a complete standalone voltage regulator. We only need to use two capacitors,

one on the input and second one on the output of 7812 in order to achieve clean voltage

output and even these capacitors are optional to use. To achieve 12V 1A current, 7812 should

be mounted on a good heat sink plate. Thanks to the transistor like shape of 7812 which

makes it easy to mount on a heat sink plate. 7812 has built in over heat and short circuit

protection which makes it a good choice for making power supplies.

FIG. 3.4 VOLTAGE REGULATOR IC 7812

30

3.2.5 TRANSISTOR

A transistor is a semiconductor device used to amplify or switch electronic signals

and electrical power. It is composed of 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 through another pair of terminals. Because the controlled

(output) power can be higher than the controlling (input) power, a transistor can amplify a

signal. Today, some transistors are packaged individually, but many more are found embedded

in integrated circuits.

FIG. 3.5 TRANSISTOR BC547

The essential usefulness of a transistor comes from its ability to use a small signal applied

between one pair of its terminals to control a much larger signal at another pair of terminals.

This property is called gain. It can produce a stronger output signal, a voltage or current, which

is proportional to a weaker input signal; that is, it can act as an amplifier. Alternatively, the

transistor can be used to turn current on or off in a circuit as an electrically controlled switch,

where the amount of current is determined by other circuit elements.

3.2.6 RESISTOR

A resistor is an electrical component that limits or regulates the flow of electrical current in

an electronic circuit. Resistors can also be used to provide a specific voltage for an active

device such as a transistor. All other factors being equal, in a direct-current (DC) circuit, the

current through a resistor is inversely proportional to its resistance, and directly proportional

to the voltage across it. This is the well-known Ohm's Law. In alternating-current (AC)

circuits, this rule also applies as long as the resistor does not contain inductance or capacitance.

31

Resistors can be fabricated in a variety of ways. The most common type in electronic devices

and systems is the carbon-composition resistor. Fine granulated carbon (graphite) is mixed

with clay and hardened. The resistance depends on the proportion of carbon to clay; the higher

this ratio, the lower the resistance.

Another type of resistor is made from winding Nichrome or similar wire on an insulating

form. This component, called a wire wound resistor, is able to handle higher currents than a

carbon composition resistor of the same physical size. However, because the wire is wound

into a coil, the component acts as an inductors as well as exhibiting resistance. This does not

affect performance in DC circuits, but can have an adverse effect in AC circuits because

inductance renders the device sensitive to changes in output.

3.2.7 BUZZER

A buzzer or beeper is an audio signaling device which may be mechanical, electromechanical,

or piezoelectric. Typical uses of buzzers and beepers include alarm devices, timers and

confirmation of user input such as a mouse click or keystroke.

FIG. 3.6 BUZZER

32

3.2.8 IC CD4047

The CD4047B is capable of operating in either the monostable or astable mode. It requires an

external capacitor (between pins 1 and 3) and an external resistor (Between pins 2 and 3) to

determine the output pulse width in the monostable mode, and the output frequency in the

astable mode. Astable operation is enabled by a high level on the astable input or low level on

the astable input. The output frequency (at 50% duty cycle) at Q and Q outputs is determined

by the timing components. A frequency twice that of Q is available at the Oscillator Output;

a 50% duty cycle is not guaranteed. Monostable operation is obtained when the device is

triggered by LOW-to-HIGH transition at + trigger input or HIGH-to-LOW transition at -

trigger input. The device can be retriggered by applying a simultaneous LOW-to-HIGH

transition to both the + trigger and retrigger inputs. A high level on Reset input resets the

outputs Q to LOW, Q to HIGH.

FIG. 3.7 IC CD4047

3.2.9 MOSFET

MOSFET (metal-oxide semiconductor field-effect transistor) is a special type of field-effect

transistor (FET) that works by electronically varying the width of a channel along which

charge carriers (electrons or holes) flow. The wider the channel, the better the device conducts.

The charge carriers enter the channel at the source, and exit via the drain. The width of the

channel is controlled by the voltage on an electrode called the gate, which is located physically

33

between the source and the drain and is insulated from the channel by an extremely thin layer

of metal oxide.

The MOSFET has certain advantages over the conventional junction FET, or JFET. Because

the gate is insulated electrically from the channel, no current flows between the gate and the

channel, no matter what the gate voltage (as long as it does not become so great that it causes

physical breakdown of the metallic oxide layer). Thus, the MOSFET has practically

infinite impedance . This makes MOSFETs useful for power amplifiers. The devices are also

well suited to high-speed switching applications. Some integrated circuits (ICs) contain tiny

MOSFETs and are used in computers.

FIG. 3.8 MOSSFET

Because the oxide layer is so thin, the MOSFET is susceptible to permanent damage by

electrostatic charges. Even a small electrostatic buildup can destroy a MOSFET permanently.

In weak-signal radio-frequency (RF) work, MOSFET devices do not generally perform as well

as other types of FET.

34

CHAPTER 4

PROJECT DESCRIPTION

4.1 DESCRIPTION OF THE CIRCUIT DIAGRAM

4.1.1 THE SOLAR BATTERY CHARGER

FIG. 4.1 THE SOLAR BATTERY CHARGER CIRCUIT

Expose the cell to light, and the energy from each photon (light particle) hitting the silicon,

will liberate an electron and a corresponding hole. If this happens within range of the electric

field’s influence, the electrons will be sent to the N side and the holes to the P one, resulting

in yet further disruption of electrical neutrality. This flow of electrons is a current; the

electrical field in the cell causes a voltage and the product of these two is power. The solar

energy is stored in the battery from Photo-Voltaic cells with the help of charging circuit.

The charging circuit is built around voltage regulator IC 7812 and two transistors BC 548.

That DC voltage is then fed to the voltage regulator IC 7812; the output will be regulated 12V.

12 volt rechargeable battery is connected at the output of voltage regulator and it charges when

main power is available.

This circuit also indicates the charging status that is the LED1 is glows when the battery is

charged (Above 10.5V). When battery voltage goes below a particular value, LED1 stops

35

glowing and the buzzer produces sound indicating that the battery has been discharged and it

needs recharge.

4.1.2 INVERTER CIRCUIT

FIG. 4.2 THE INVERTER CIRCUIT

This circuit is DC to AC inverter, where the circuit work based on the stable multi-vibrator

does. On this circuit using CD4047 IC as the heart of multi-vibrator that functions to generate

a wave 50Hz is not stable, because this type of IC to provide a complementary output stage,

contrary to the other (pins 10 and 11, as shown), and 50% of the cycle to meet the obligation

to produce pulse inverter.

Circuit is called a simple DC to AC inverter, as there is no output signal is not sinusoidal, and

there were lots of harmonic signals on the output. To suppress this signal we have to use a

filter such as capacitor C. Because of this simplicity is only suitable circuits for lighting needs.

To build a sinusoidal inverter DC to AC. At the circuit this multivibrator is used to make

power is too high, then we have to use the MOSFET IRFZ44. IRFZ44 provide high current to

drive step-up transformer, so power is available in addition to the high voltage transformer.

36

The power MOSFETs are connected in Push Pull configuration (Power amplifier). The

MOSFETs will switch according to the pulse from CD4047 astable multivibrator. Thus an AC

voltage is transferred to the primary of transformer; it is stepped up to 230V.

The transformer used here is an ordinary step down transformer which is connected in inverted

manner. That is, the primary of a 230V to 12V-0-12V step down transformer can be treated

as secondary for this inverter project.

This circuit uses 12V input (12V battery) to out 220V 50HZ. For safety please note for the

installation of cooling on the components transistors, it serves to remove excess heat transistor.

37

CHAPTER 5

PCB DESIGNING

5.1 INTRODUCTION

A PCB is used to mechanically support and electrically connects electronic components using

conductive pathways, tracks or etched from copper sheets. It is also referred to as PWB. A PCB

populated with electronic components is PCA, also known as a PCBA. PCB is inexpensive,

and can be highly reliable. They require much more layout effort and higher initial cost than

either wire-wrapped or point-to-point constructed circuits, but are much cheaper and faster for

high-volume production. One of the most discouraging things about making a hardware project

is building PCB. Due to the improvements in printing technologies it is now relatively easy to

make inexpensive high quality PCB's at home.

PCB stands for Printed Circuit Board. It is of two types:

1) General purpose - It is already drilled and etched.

2) Special purpose - It requires step by step process of making layout then etching and

then drilling.

5.2 PCB CONSTRUCTION

The different processes that take place in the fabrication of a PCB are as follows:-

1. Layout designing

2. Transfer of pattern on copper board.

3. Drying

4. Etching

5. Tinning

6. Drilling

7. Soldering

8. Surface cleaning

9. Final inspection of PCB

38

5.2.1 LAYOUT DESIGNING

First of all layout design of the circuit switch, to be traced on the PCB, is prepared. The layout

of a PCB has to incorporate all the information on the board; one can go to the art of work

preparation. The detailed circuit diagram is very important for the layout designer but one must

also have familiar with the design concept & with the philosophy behind the equipment. In this

process the layout designer, traces the circuit on a graph paper. By this process he/she marks

where the holes should be. Thus the circuit, which is to be traced on the PB, is firstly traced on

the graph paper or its layout is designed. In layout designing the distance between the copper

tracks & length, size etc. of components are also taken into consideration.

FIG. 5.1 – CIRCUIT ON CIRCUIT WIZARD SCREEN

5.2.2 TRANSFER OF PATTERN

After designing the art work on the graph paper, we transferred it onto the trace paper. The

conductor pattern is then transferred to the copper clad lamination with the help of carbon

paper. By this, the pattern gets transferred on the copper clad lamination.

39

FIG. 5.2 – CIRCUIT LAYOUT

5.2.3 ETCHING

Etching is done to remove all the unwanted copper which is present on the portion other than

the pattern on the PCB. For this the PCB is kept dipped in the solution (FeCl2) and two or three

drops of HCL. The chemicals react with copper & dissolve it. After some hours of time we get

the PCB left with only copper tracks on it.

5.2.4 TINNING

The board is tinned using a soldering iron and a small piece of tinned solderwick. Tinning isn't

absolutely necessary but it improves the appearance of the board and prevents the copper from

oxidizing before it's time to solder the parts to the board.

40

5.2.5 DRILLING

Drilling of component mounting holes into PCB is the most important mechanical matching

operation in PCB production process. Holes are made by drilling where ever a superior hole

finish in is required. Therefore, drilling is applied by all the professional grade PCB

manufacturers & generally in all smaller PCB production plants & laboratories.

5.2.6 SOLDERING

Soldering is the process of joining two metallic conductors, the joint where the two metallic

conductors are to be joined or fused is heated with a device called soldering iron and then an

alloy of tin and lead called solder is applied which melts and cover the joint. The solder cools

and solidifies quickly to ensure a good and durable connection between the joined metals.

Covering the joint with solder prevents oxidation.

EQUIPMENTS REQUIRED - The various tools and equipments required for construction of

a PCB are given below:-

a) Solder kit consist of:-

i) Soldering iron.

ii) Soldering wire.

iii) Flux

b) Tweezers

c) Cutter

d) Multi-meter (Measuring instrument)

PRECAUTIONS FOR PRACTICAL –

i. The quantity of soldering of component on PCB should be good quantity.

ii. The component fitted on the PCB should loosely fit.

iii. Use ferric chloride safely.

iv. Add ferric chloride to the water, not water to the ferric chloride.

41

5.2.7 SURFACE CLEANING

After drilling, the surface is cleaned so that the scraps may be removed which are settled on

the board during drilling.

5.2.8 FINAL INSPECTION OF PCB

After complete fabrication, PCB is inspected for any defect such as short circuit or open circuit.

If no defect found, then the PCB will be directly considered for operation.

42

CHAPTER 6

COST ESTIMATION AND APPLICATIONS

Usage of solar energy and especially installation of photovoltaic systems has increased

throughout the last years affected by many reasons such as: the increased rate of the price of

electricity utilizing fuel and diesel oil, the improvements in techniques used for installing solar

systems, increase in efficiency of solar systems etc.

On the other hand, due to the equipment required, PV power generation is more expensive than

other resources. Governments are promoting it with subsidies or feed-in tariffs, expecting the

development of the technology so that in the near future it will become competitive. Increasing

the efficiency in PV plants so as to increase the power generated is a key aspect, as it will

increase the incomes, reducing the cost of the power generated, cost approaching the cost of

the power produced from other sources.

This increase in the usage of solar energy has led to a dramatic decrease in the prices of this

renewable energy. It is reported that the prices are declining at a rate of 4% per annum and over

the last 15 years.

Although installing a PV system costs a considerable amount of money, these systems can be

of economic benefit in the long run. This is due to the fact that a big amount of money is paid

once to purchase the system after which the annual costs are limited to maintenance, and

upgrading the power delivery system. The annual costs are very small compared to costs you

pay for running a diesel engine (maintenance, fuel etc...), and they range between 0.02 and 0.1

cents/kWh.

In the future, when the prices of fossil fuels rise and the economic advantages of mass

production reduce the peak watt cost of the photovoltaic cell, photovoltaic power will become

more cost competitive and more common.

43

6.1 COST ESTIMATION OF THE PROJECT

S. No Component Ratings Cost

1. THE SOLAR BATTERY CHARGER

viii. Step Down Transformer 230V/12V, 1A 70/-

ix. Diodes IN4001, IN 4007 4/-

x. Capacitors 470µF, 50V 5/-

xi. Voltage regulator IC 7812 IC 7812 30/-

xii. Transistor BC547 40/-

xiii. Resistors (Each 0.25 watt) 10kΩ,1.5kΩ,100kΩ 10/-

xiv. Buzzer 12V 27/-

2. INVERTER

vi. IC CD4047 CD4047 45/-

vii. Resistors 1K, 18K, 100Ω 5/-

viii. Capacitor 0.22µF 10/-

ix. MOSFET IRFZ44 40/-

x. Step Down Transformer 230V/12V,5A 70/-

3. Battery 12V,4.5Ah 700/-

4. Solar Plate 6W 700/-

5. Miscellaneous 300/-

TOTAL 2056/-

6.2 APPLICATIONS OF SOLAR INVERTER

6.2.1 DC POWER SOURCE UTILIZATION

An inverter converts the DC electricity from sources such as batteries, solar panels, or fuel

cells to AC electricity. The electricity can be at any required voltage; in particular it can operate

AC equipment designed for mains operation, or rectified to produce DC at any desired voltage.

44

6.2.2 UNINTRRUPTABLE POWER SUPPLY

An uninterruptible power supply (UPS) uses batteries and an inverter to supply AC power

when main power is not available. When main power is restored, a rectifier supplies DC power

to recharge the batteries.

6.2.3 HVDC POWER TRANSMISSION

With HVDC power transmission, AC power is rectified and high voltage DC power is

transmitted to another location. At the receiving location, an inverter in a static inverter

plant converts the power back to AC.

6.2.4 THE GENERAL CASE

A transformer allows AC power to be converted to any desired voltage, but at the same

frequency. Inverters, plus rectifiers for DC, can be designed to convert from any voltage, AC

or DC, to any other voltage, also AC or DC, at any desired frequency. The output power can

never exceed the input power, but efficiencies can be high, with a small proportion of the power

dissipated as waste heat.

6.3 ADVANTAGES

1. Constant and uninterrupted supply.

2. There is no requirement of electricity and manpower to operate the device.

3. With no moving parts involved, its efficiency is further enhanced.

4. It acts as a power back up solution.

5. Circuit can be checked with 12 volt (DC) universal power supply.

6. It is one of the methods of renewable generation.

7. This is an ecofriendly means of power generation.

8. It can be used in distant villages where transmission cost is much high.

9. Reduction in consumption from conventional sources of energy.

45

6.4 DISADVANTAGES

1. Initial cost of installation is very high.

2. Area required for installation is large.

3. It will be less effective in rainy days.

4. Protection system installment is very high.

5. Cause problems to eye sight because of solar reflectors.

46

CONCLUSION

Photovoltaic power production is gaining more significance as a renewable energy source due

to its many advantages. These advantages include everlasting pollution free energy production

scheme, ease of maintenance, and direct sunbeam to electricity conversion. However the high

cost of PV installations still forms an obstacle for this technology. Moreover the PV panel

output power fluctuates as the weather conditions, such as the insolation level, and cell

temperature.

The described design of the system will produce the desired output of the project. The inverter

will supply an AC source from a DC source.

The project described is valuable for the promising potentials it holds within, ranging from the

long run economic benefits to the important environmental advantages. This work will mark

one of the few attempts and contributions in the Arab world, in the field of renewable energy;

where such projects could be implemented extensively. With the increasing improvements in

solar cell technologies and power electronics, such projects would have more value added and

should receive more attention and support.

47

FUTURE SCOPE

As whole world is facing a problem of global warming and energy crisis, our project will help

to reduce these problems by using solar energy to generate electricity. Solar energy is an infinite

source of energy. Main motto of our project is to promote use of renewable energy sources.

This project is most useful in our life because in this project one time investment fixed on life

time. In future one day nonrenewable energy will end then we will use to the renewable energy.

The solar inverter made by us is just a prototype for making future projects which incorporate

advanced technologies like micro controlled solar tracking, charge control, etc. this is to show

that solar inverters are very cheap and easy to install so that the energy demands are shifted on

using renewable sources of energy. There is more advancements pending in this field which

will revolutionise the energy stream and solar energy will be playing the most important role

of all.

48

REFERENCES

The reference of the books and websites, we have referred in order to complete my training

report are as follows:-

[1] Khan, B.H.: Non-Conventional Soures of Energy, 5/e, Mc Graw Hill Education(India).

[2] Van Valkenburg, M.E. : Network Analysis, 3/e, Mc Graw Hill Education (India).

[3] Milliman, Jacob & Christos Halkias: Integrated Electronics, 2/e, Mc Graw Hill

Education(India).

[4] Gupta, J.B. : Electronics Devices & Circuit, 3/e, S.K. Kataria & Sons, 2009.

[5] Salivahanan, S. & S. Arivazhagan: Digital Electronics, 3/e, Vikas Publication, 2007.

[6] Fitzgerald, A.E., Charles Kingsley & Stephen D. Umans : Electric Machinery, 3/e, Mc

Graw Hill Publication (India).

[7] Hussain, Ashfaq : Electrical Machines, Second Edition, Dhanpat Rao Publications.