hydro power generation system

8/12/2019 Hydro Power Generation System

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Hydro power generation system

ABSTRACT

Hydro Power Project may be used as one of the option for achieving the energy

targets in a developing country like India where center or state Governments have

limited financial resources to put in large projects which require long gestationperiod. One additional advantage with the mall Hydro Power. Project is that

private partners may get attracted due to low investment and quicker return in

comparison to large projects. !he last but not least is the most eco friendliness of

small power projects which is a point of serious concern in case of thermal" or

nuclear or sometimes in big Hydro power projects depending upon the location of

the projects. mall Hydro Power potential in India is still under#utili$ed and there

is need to tap this potential for optimum utili$ation of natural resources. In %adhya

Pradesh" mall hydro plants are not many " however there is good scope for

developing such plants. !awa is one of such plants in %P" which has beendeveloped as canal head powerhouse on the left bank canal &'()* of !awa

irrigation project by a private investor. !his plant is working in a very efficient

manner addressing both the power and irrigation aspects successfully. !his

e+ample will attract the private investments in small hydropower sector in the

developing countries like India.

Introduction:

Hydropower is a renewable" non#polluting and environment friendly source ofenergy. It is perhaps the oldest energy technique known to mankind for conversion

of mechanical energy into electrical energy. Hydropower represents use of water

resources towards inflation free energy due to absence of fuel cost. Hydropower

contributes around ,, - of the world electricity supply generated. !he total

potential of small Hydropower of the whole world is /0"000 %1 out of which

20"000 %1 has already been utili$ed. mall Hydro is also the highest density

resources in generation of electricity due to the reason of being it environment

friendly" fle+ibility in operation and suitability in giving support in peak time to the

local grid. 3ue to the small gestation period" small capital investment and quickerreturn involved" in recent years it has become the point of attraction for private

sector 4iscal incentive announced by the central and state Governments time to


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in minimum time. 5nd offers the fastest economical means to enhance power

supply" improve living standards" stimulate industrial growth and enhance

agriculture with the least environmental impact and without heavy transmission

losses .3ue to less transmission losses there is a reduction in distribution cost as

well. Its availability at the head of the irrigation canals and small streams is also aone of the added advantage of it.

(lock 3iagram

water

Propeller system

(attery charger

battery

3c generator

3c out put


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HISTORY OF HYDROPOWER

!he first hydroelectric power dam in the world was built in 5ppleton" 1isconsin in

67/,. In India" 8amshed ji !ata built the first hydroelectric power dam in the

1estern Ghats of %aharashtra in the early 6700s to supply clean power to

(ombay9s )otton and !e+tile %ills. He took the (ritish Government9s permission

to build dams" namely the 5ndhra" irowata" :alvan and %ulshi hydel dams in the

1estern Ghats to generate electricity using high rainfalls in the hills as storage

areas. Humans have been harnessing water to perform work for thousands of years.

!he Greeks used water wheels for grinding wheat into flour more than ,"000 years

ago. (esides grinding flour" the power of the water was used to saw wood andpower te+tile mills and manufacturing plants. 4or more than a century" the

technology for using falling water to create hydroelectricity has e+isted. !he

evolution of the modern hydropower turbine began in the mid#600s when a

4rench hydraulic and military engineer" (ernard 4orest de (elidor wrote

5rchitecture Hydraulique. In this four volume work" he described using a vertical#

a+is versus a hori$ontal#a+is machine. 3uring the 600s and 6/00s" water turbine

development continued. In6//0" a brush arc light dynamo driven by a water turbine

was used to provide theatre and storefront lighting in Grand ;apids" %ichigan< and

in 6//6" a brush dynamo connected to a turbine in a flour mill provided streetlighting at =iagara 4alls" =ew >ork. !hese two projects used direct#current

technology.

Hydropower in India

1ith the liberali$ation of the economy" the Government of India has been

encouraging and invited private sector for investment in the power sector.

5ccordingly" a conducive policy environment has been created by modifying the

?lectricity 5ct. !he new ?lectricity 5ct#,00@ deals with the laws relating to

generation" transmission" distribution" trading and use of electricity. !he 5ct has

specific provisions for the promotion of renewable energy including hydropower

and cogeneration. It has been made mandatory that every state regulatory

commission would specify a percentage of electricity to be purchased from

renewable by a distribution licensee. !he =ational ?lectricity Policy announced in

,002 aims at access of electricity by all households and per capita availability of

electricity to be increased to 6000 units by ,06,. !he Policy underlines that


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government has announced !ariff Policy in ,00A wherein the tate ;egulatory

)ommissions are required to fi+ tariff in their respective state and also decide

about the renewable purchase obligation. !he ?lectricity 5ct and !ariff Policy are

favorably tilted towards increasing power generation from renewable. =ow"

)entral ?lectricity ;egulatory )ommission has also announced the tariffcalculation guidelines for renewable technologies including for small hydro

projects. !he e+isting power deficit and a rapid growing demand coupled with

government commitment to provide access to electricity for all has necessitated a

large scale capacity addition program. 5 capacity addition of /"000 %1 in the

66th Plan &,00 to ,06,* and appro+imately one 600"000 %1 in the 6,th Plan

&,06,#,06* is planned. )oncurrent investments in !ransmission and 3istribution

are also going on. uch a gigantic task is strongly supported and complemented by

the private sector. !hese changes facilitated the removals of barriers to investment"

improved the functioning of the system and resulted in additional generation ofpower much in e+cess of that achieved in the earlier plans. %inistry of =ew B

;enewable ?nergy &%=;?* Government of India is the nodal ministry for small

hydropower development in India.

HYDROELECTRIC PROECTS DE!ELOP"E#T: CHALLE#$ES

?nhancing the level of energy consumption" particularly in less developed and

developing countries" is a global challenge. ,0- of world population living inindustriali$ed countries consumes A0- of energy and remaining /0- of population

has to manage within C0- of total energy. !his has obviously resulted in wide

disparities between the standard of living and quality of life of high energy

consuming countries on the one hand and those who do not have the opportunities

of adequate access to energy on the other. It is precisely for this reason that

development of different sources of energy and increase in its consumption has

become a priority agenda of all the developing countries. :arious countries have

adopted their own strategies to provide energy to their people. In the conte+t of

electric power" as an important form of energy" the thermal and hydroelectricpower on a global basis" have occupied the largest proportion. 1ithin the thermal

group" coal based power stations occupy dominant position. However" this varies

from country to country. !he Gas based combined cycle power stations in number

of countries occupy a significant proportion. imilarly" nuclear power stations have

also increased and have been adding large amount of capacity to the thermal group.

3uring last @0 years" Hydroelectric power generation has" as a matter of fact"

reduced from ,6- in 67@ to less than 6- in ,000. 3uring the same period" coal

based generation marginally increased from @/- to @7-" gas increased

substantially from 6,- to 6.C- and nuclear witnessed a very steep rise from

@.@- to 6A.7-. Obviously concerted efforts are required to develop Hydroelectric

capacities.


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Low E%p&oitation o' Hydro Potentia& :

Inspite of hydroelectric power requiring a clean energy generation process"e+ploitation of Hydroelectric potential in various countries has been rather on a

lower side. D

Power S(orta)e in India:

In India" though over 600"000 %1 of capacity has been added in last 20

years" there is a huge gap between the demand and supply of power. 1hile in

the last few years it has marginally reduced" the peaking shortage continues tobe over 6,- to 6@- and the average energy shortage at about /./-. Indian

power system has an installed capacity of 60/",0 %1 in %ay ,00@" with

hydroelectric accounting for ,2-.

Dec&inin) proportion o' Hydro Capacity:

In the last @0 years" the proportion of hydroelectric capacity in the Indianpower system has considerably reduced. It has dropped from about CA- in

670 to C0- in 67/0" ,7- in 6770 and now ,2- in ,00@. In spite of theHydroelectric potential" which is now estimated to be of the order of 620"000

%1" the e+ploitation has been of the order of ,"000 %1. ome of the

important reasons for decline in the Hydroelectric proportion in the total

capacity over the last @0 years are as followsD a* Indian power supply industry

has always e+perienced the situation of shortages both in energy and peaking

requirements. !o tide over the shortage in shortest possible time" more

dependence was placed on sources of power generation with shorter gestation

period. Obviously this short#term approach rather than a long#termperspective led to this problem. b* 1ith abundant coal reserves in the

country" large capacity additions through coal based pithead power stations

during the eighties and nineties increased the thermal proportion. c*

?mergence of gas based combined cycle power stations based on indigenous

natural gas with gestation period of ,#, E years also received priority in

response to the an+iety to create capacity addition in shortest possible time. d*

=uclear power stations have also emerged as reliable modes of thermal

generation. e* In spite of best efforts at the stage of planning and formulating

projects in the hydro segment" a number of large projects got into longgestation period of construction on account of various reasons" namely


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successful stories on the hydroelectric projects but we also have large projects

which have taken several years to get completed.

T(ru*t on Hydro Power:

In the recent years" the Govt. of India has committed quantum jump" in the

financial allocation and also by way of other supports so that Hydroelectric

projects not only get right priorities but also contribute in an increased way to

the future capacity addition programs of the country. 5ccordingly" in the 60 th

4ive#>ear Plan &year ,00,#,00*" the target for hydroelectric capacity has

been placed 6C"@7@ %1" which is more than the total installed capacity

&6@"AAA %1* created in the last ,0 years. !he thrust on hydroelectric

development is based on the following considerationsD a* Hydroelectric

involves a clean process of power generation. Once the projects are

constructed" there is no pollution ramification unlike many other power

generation technologies and processes. b* ince it does not suffer from the

limitation of inflation on account of fuel consumption" in the long run" it is

the most cost#effective option for power supply. In Indian conte+t" where

more than C2- of Indian population has yet to have access to electricity at an

affordable price" this is an important consideration. c* Indian power supply

system has a peculiar limitation of huge variation between peak and off peak

requirements. %anagement of peak load in an effective manner could beconveniently handled through availability of hydroelectric support. !he

system at present does suffer from large frequency variations. (etter hydro

support could address this problem better.

d* 'ocations of Hydroelectric projects in India are also in areas which need

substantial support for their economic development. !hese areas are =orth#

east" Fttaranchal" Himachal Pradesh B 8ammu B ashmir where more than

/0- of potential e+ists. 3eveloping projects in these areas will spur

economic activities and will lead to overall economic development. e* In an

integrated Hydroelectric project there are many such projects the schemesinvolve not only supply of electricity but also provision of drinking water and

irrigation. !hese are important issues in many parts of India. Hydroelectric

projects" in many cases" do have the ability to mitigate these problems. f*

4lood control is also an issue and quite often a challenge. Integrated

hydroelectric projects could adequately address this concern.


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$o+t, o' India Initiati+e on Hydro Power De+e&op-entD!he main features of the Government of India policy on hydro powerdevelopment are as followsD 5dditional budgetary financial support for

ongoing and new hydro projects under )entral Public ector Fndertakings.

(asin#wise development of hydro potential comprehensive ;anking

studies for @77 schemes.

5dvance action for capacity addition 60 year ahead of e+ecution

?mphasis on quality of survey B investigations ;esolution of inter#state issues on sharing of water and power.

;enovation" %oderni$ation B Fprating of e+isting hydro stations

Promoting small and mini hydel projects ,2 %1 and below now fall into

category of non#conventionalJ qualifying for benefits.

implified procedures for clearances by )entral ?lectricity 5uthority3;O?'?)!;I) P;O8?)! 3?:?'OP%?=!D )H5''?=G? 5=3

;?PO=? M

;: H5HI" ?);?!5;>

%I=I!;> O4 PO1?;" GO:!. O4 I=3I5

?nhancing the level of energy consumption" particularly in less developed

and developing countries" is a global challenge. ,0- of world population

living in industrialised countries consume A0- of energy and remaining /0-

of population have to manage within C0- of total energy. !his has

obviously resulted in wide disparities between the standard of living and

quality of life of high energy consuming countries on the one hand and those

who do not have the opportunities of adequate access to energy on the other.

It is precisely for this reason that development of different sources of energy

and increase in its consumption has become a priority agenda of all the

developing countries.


9/47

,. :arious countries have adopted their own strategies to provide energy to

their people. In the conte+t of electric power" as an important form of

energy" the thermal and hydroelectric power on a global basis" have

occupied the largest proportion. 1ithin the thermal group" coal based power

stations occupy dominant position. However" this varies from country to

country. !he Gas based combined cycle power stations in number of

countries occupy a significant proportion. imilarly" nuclear power stations

have also increased and have been adding large amount of capacity to the

thermal group. 3uring last @0 years" Hydroelectric power generation has" as

a matter of fact" reduced from ,6- in 67@ to less than 6- in ,000. 3uring

the same period" coal based generation marginally increased from @/- to

@7-" gas increased substantially from 6,- to 6.C- and nuclear witnessed a

very steep rise from @.@- to 6A.7-. Obviously concerted efforts are required

to develop Hydroelectric capacities

*PAPER FOR VALEDICTORY SESSION IN INTERNATIONAL CONFERENCEON LARGE DAMS (ICOLD) AT MONTREAL, 17-20, JUNE, 2003


10/47

., Low E%p&oitation o' Hydro Potentia&

Inspite of hydroelectric power requiring a clean energy generation process" e+ploitation of

Hydroelectric potential in various countries has been rather on a lower side. 1hile the

countries like )anada B =orway have e+ploited their hydro potentials to the e+tent of

C/- and 2/- respectively" (ra$il has developed it to the e+tent of @6-" )hina and India

both only to the e+tent of 6/-.

/"W0CO1#TRY POTE#TIAL I#STALLED PERCE#TA$E

=orway C"000 ,"@A0 2/

)anada 6A0"000 A2"@/ C/

(ra$il 60"000 2,"C, @6

)hina @60"000 2A"000 6/India 620"000 ,"000 6/

2, Power S(orta)e in India

In India" though over 600"000 %1 of capacity has been added in last 20

years" there is a huge gap between the demand and supply of power. 1hile

in the last few years it has marginally reduced" the peaking shortage

continues to be over 6,- to 6@- and the average energy shortage at about

/./-. Indian power system has an installed capacity of 60/",0 %1 in %ay

,00@" with hydroelectric accounting for ,2-.

In*ta&&ed Capacity in "W /345633.0

Sector Hydro T(er-a& Wind #uc&ear Tota&

tate ,@"0/2 C0"6C6 A2 0 A@",76Private /A 7"C67 6/02 0 6,"600

)entral @0C7 ,"0C 0 ,,0 @,"/6A

!otal ,"060 A"A0 6"/0 ,,0 6"0/",0


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4, Dec&inin) proportion o' Hydro Capacity

In the last @0 years" the proportion of hydroelectric capacity in the Indian

power system has considerably reduced. It has dropped from about CA- in

670 to C0- in 67/0" ,7- in 6770 and now ,2- in ,00@. In spite of the

Hydroelectric potential" which is now estimated to be of the order of 620"000

%1" the e+ploitation has been of the order of ,"000 %1. ome of the

important reasons for decline in the Hydroelectric proportion in the total

capacity over the last @0 years are as followsD

a* Indian power supply industry has always e+perienced the situation of

shortages both in energy and peaking requirements. !o tide over the shortage

in shortest possible time" more dependence was placed on sources of power

generation with shorter gestation period. Obviously this short#term approach

rather than a long#term perspective led to this problem.b* 1ith abundant coal reserves in the country" large capacity additions through

coal based pithead power stations during the eighties and nineties increased

the thermal proportion.

c* ?mergence of gas based combined cycle power stations based on indigenous

natural gas with gestation period of ,#, E years also received priority in

response to the an+iety to create capacity addition in shortest possible time.d* =uclear power stations have also emerged as reliable modes of thermal

generation.

e* In spite of best efforts at the stage of planning and formulating projects in the

hydro segment" a number of large projects got into long gestation period of

construction on account of various reasons" namely environmental issues"

rehabilitation B resettlement &;B;* problems" gap between investigations

and field realities" etc. 1e do have a number of successful stories on the


12/47

A. T(ru*t on Hydro Power

In the recent years" the Govt. of India has committed quantum jump" in the

financial allocation and also by way of other supports so that Hydroelectric

projects not only get right priorities but also contribute in an increased way

to the future capacity addition programmes of the country. 5ccordingly" in

the 60th 4ive#>ear Plan &year ,00,#,00*" the target for hydroelectric

capacity has been placed 6C"@7@ %1" which is more than the total installed

capacity &6@"AAA %1* created in the last ,0 years. !he thrust on

hydroelectric development is based on the following considerationsD

a* Hydroelectric involves a clean process of power generation. Once the

projects are constructed" there is no pollution ramification unlike many other

power generation technologies and processes.

b* ince it does not suffer from the limitation of inflation on account of fuel

consumption" in the long run" it is the most cost#effective option for power

supply. In Indian conte+t" where more than C2- of Indian population has yet

to have access to electricity at an affordable price" this is an important

consideration.

c* Indian power supply system has a peculiar limitation of huge variation

between peak and off peak requirements. %anagement of peak load in an

effective manner could be conveniently handled through availability of

hydroelectric support. !he system at present does suffer from large

frequency variations. (etter hydro support could address this problem better.

d* 'ocations of Hydroelectric projects in India are also in areas which need

substantial support for their economic development. !hese areas are =orth#

east" Fttaranchal" Himachal Pradesh B 8ammu B ashmir where more than

/0- of potential e+ists. 3eveloping projects in these areas will spur

economic activities and will lead to overall economic development.

e* In an integrated Hydroelectric project there are many such projects theschemes involve not only supply of electricity but also provision of drinking


13/47

Hydroelectric projects" in many cases" do have the ability to mitigate these

problems.

f* 4lood control is also an issue and quite often a challenge. Integrated

hydroelectric projects could adequately address this concern.

. $o+t, o' India Initiati+e on Hydro Power De+e&op-entD

!he main features of the Government of India policy on hydro power

development are as followsD

5dditional budgetary financial support for ongoing and new hydro

projects under )entral Public ector Fndertakings.

(asin#wise development of hydro potential comprehensive ;anking

studies for @77 schemes.

5dvance action for capacity addition 60 year ahead of e+ecution

?mphasis on quality of survey B investigations

;esolution of inter#state issues on sharing of water and power.

;enovation" %oderni$ation B Fprating of e+isting hydro stations

Promoting small and mini hydel projects ,2 %1 and below now fall

into category of non conventionalJ qualifying for benefits.

implified procedures for clearances by )entral ?lectricity 5uthority

T

1hereD

' > 're=uency in Hert? / CPS 0< > con*tantT > periodic ti-e / t(e ti-e in w(ic( one cyc&e i* co-p&eted 0


25/47

E%a-p&e < !o&t.

Root "ean S=uare !a&ue o' a Wa+e'or-

If you measure the mains supply you will find it to be ,@0 :olts.!his is the Root"ean S=uare& ;% * value of the alternating voltage. It is also known as the E''ecti+evalue.!he ;% value of the waveform in 4igure A is 0.0 :olt.!his may be written as !R"S > 3,3 !o&t.

!he ;% value of an 5) voltage orcurrent is defined as the equivalent 3) value" which would have the *a-e(eatin) e''ect. !he ;% or ?ffective value is the value normally used. 5ll multimeters are designed to read ;%values.

A+era)e !a&ue o' a Wa+e'or-

!he A+era)evalue of a waveform is calculated over one half of a cycle. It is also known as the "eanvalue. !heaverage value of the waveform in 4igure A is 0.A@ :olt. !his may be written as !A!E > 3,@. !o&t. It is simply the

mathematical average value of the positive ornegative half cycle. If an attempt is made to average an alternatingwaveform over a complete cycle" the negative half of the waveform will cancel the positive half" and so the result is$ero.


27/47

Re&ation*(ip Between Wa+e'or- !a&ue*

If you measure the mains supply with a multimeter you will find it to be about ,@0 :olts. ;emember" this is the;% value. 4rom this" the peak value can be calculated as followsD

;% :alue

Peak :alue

0.0

,@0

Peak :alue

0.0

Peak :alue .64 !o&t*

!he Peak or%a+imum :alue of the ,@0 :olt mains supply is about @,2 :olts. Please note that @,2 :olts will beacross your body if you receive an electric shock from the ,@0 :olt mains.

=ow that we know the peak value of the supply" the average value can be calculated as followsD

5verage :alue Peak :alue + 0.A@

5verage :alue @,2 + 0.A@

5verage :alue 63 !o&t*

!he average or mean value is rarely used" e+cept in some electronic circuits" e.g. rectifier circuits.

Given the peak value of the supply" the ;% value may be calculated as followsD

;% :alue Peak :alue + 0.0

;% :alue @,2 + 0.0

;% :alue 6.3 !o&t*

Given the average value of the supply" the peak value may be calculated as followsD

5verage :alue

Peak :alue

0.A@

,0

Peak :alue

0.A@

Peak :alue .64 !o&t*


28/47

E%a-p&e

!he peak value of a sine wave is 6, :olts and it has a periodic time of 6A m.)alculate the followingD

&6* ;% value

&,* 5verage value of full wave&@* 5verage value of half wave

&C* 4requency of supply.

So&ution&6* ;% value Peak value + 0.0

;% value 6, + 0.0

;% value ,22 !o&t*

&,* 5verage value of full wave 0" since the negative half cancels the positive half e+actly.

&@* 5verage value of half wave

5verage value Peak value + 0.A@

5verage value 6, + 0.A@

5verage value ,@22 !o&t*,

&C* 4requency of upply

6

f ! 6A m 6A + 60#@ m

!

6

f

6A + 60#@

60@

f

6A

6000

f

6A

f @6,4 H?


29/47

Purely Resistive AC Circuits

E''ect o' Re*i*tance in DC and AC Circuit*

Purely resistance circuits consist of electrical devices" which contain no inductance or capacitance. 3evices such asresistors" lamps & incandescent * and heating elements have negligible inductance or capacitance and for practical

purposes can be considered to be purely resistive. 4or such 5) circuits the same rules and laws apply as for 3)circuits.

;efer to 4igure .

A

Resistor,R

+

!,'DC

Fi)ure F

I

;

60I

600

I 3,


30/47

T(e E''ect o' Capacitance in DC and AC Circuit*

4igure shows a DC *upp&y connected to a non polarised capacitor. 1hen the supply is

switched on" the ammeter will indicate current flowing initially" and then the reading will fall off

to $ero. !his indicates that the capacitor is charged. (ecause there is virtually no resistance in the

circuit" the charging of the capacitor is almost instantaneous.

In a DC circuit containin) on&y capacitance7 no current '&ow* a'ter t(e initia& c(ar)in)

current,

A

C a p a c i t o r

+

!

Fi)ure

4igure / shows a lamp connected in series with a non#polarised capacitor across 6, : 3) supply. 1hen the switchis closed" the lamp may flicker onJ for an instant as the charging current flows through it.

!his current flow reduces to $ero as the capacitor charges to full capacity. 5t this stage the

applied voltage is across the terminals of the capacitor and the voltage across the lamp has

reduced to $ero.


31/47

. a m p

+

!

, / ' D C

S & i t c h

C a p a c i t o r

Fi)ure


32/47

4igure 7 shows the same circuit now connected to an AC *upp&y,

1hen the switch is closed" the capacitor is charged with one polarity and then it discharges< ne+t the capacitor is

charged with the opposite polarity" and then it discharges again.

!he cycles of charge and discharge current provide an alternating current in the circuit" at the

same frequency as the applied voltage. !his is the current" which lights the lamp.

. a m p

S & i t c h

C a p a c i t o r

, / ' A CR $ S ' a l u e

Fi)ure

4igure 60 shows the same circuit with a lower value capacitor. !his capacitor takes a lower value charge anddischarge current and therefore the lamp will be dimmer. !he lower value capacitor has more opposition to

alternating current and so less current flows in the circuit. 4rom this we can see that the circuit has -ore reactance'or &e** capacitance,

. a m p

S & i t c h

C a p a c i t o r

, / ' A CR $ S ' a l u e

Figure 10

Capaciti+e Reactanceis the oppo*itionoffered to the flow of a&ternatin) currentin a circuit containing acapacitor.

Reactance

)apacitive ;eactance is measured in O(-*and is denoted in a circuit by the symbol C.


33/47

Su--ary:

1hen 3) is applied to a circuit containing a capacitor in series with a lamp" the capacitor acts" as a

blocking device and the lamp does not light.

1hen 5) is applied to a circuit containing a capacitor in series with a lamp" the capacitor allows current toflow through the process of charging and discharging the capacitor and as a result the lamp illuminates.

In an 5) circuit containing a capacitor" the lower the capacitance value the lower the current flow. !his

means that" the lower the capacitor value" the greater the opposition to current flow. !his opposition isknown as )apacitive ;eactance & L) *.

5 discharged capacitor behaves like a closed switch.

5 charged capacitor behaves like an open switch.


34/47

Introduction and Hi*tory:

5n electric generator is a device used to convert mechanical energy into electrical

energy.

!he generator is based on the principle of electromagnetic induction discovered in

6/@6 by %ichael 4araday. 4araday discovered that if an electric conductor" like a

copper wire" is moved through a magnetic field" electric current will flow in the

conductor. o the mechanical energy of the moving wire is converted into the

electric energy of the current that flows in the wire.

!o change the imple Generatorinto a direct#current generator" we have to do the

followingD

6. !he current must be made to move in only one direction.

,. !he current must be conducted from the rotating loop of wire
http://www.k12.nf.ca/gc/scienceweb/physicsweb/Physics3204/studentprojs/Project26/principles.htmhttp://www.k12.nf.ca/gc/scienceweb/physicsweb/Physics3204/studentprojs/Project26/principles.htm


35/47

$enerator co-ponent*

5 3) generator consist of the following components

Rotor:

In its simplest form" the rotor consists of a single loop of wire made to rotate within a magnetic

field. In practice" the rotor usually consists of several coils of wire wound on an armature.

Ar-ature:

!he armature is a cylinder of laminated iron mounted on an a+le. !he a+le is carried in bearings

mounted in the e+ternal structure of the generator. !orque is applied to the a+le to make the rotor

spin.

Coi&:

?ach coil usually consists of many turns of copper wire wound on the armature. !he two ends of

each coil are connected either to two slip rings &5)* or two opposite bars of a split#ring

commutator &3)*.

Stator:

!he stator is the fi+ed part of the generator that supplies the magnetic field in which the coils

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

around the rotor. 5lternatively" the magnetic field may be provided by two electromagnets.

Fie&d e&ectro-a)net*:

?ach electromagnet consists of a coil of many turns of copper wire wound on a soft iron core.

!he electromagnets are wound" mounted and shaped in such a way that opposite poles face each

other and wrap around the rotor.

Bru*(e*:

!he brushes are carbon blocks that maintain contact with the ends of the coils via the slip rings&5)* or the split#ring commutator &3)*" and conduct electric current from the coils to the

e+ternal circuit


36/47

How DC $enerator* Wor:

!he commutator rotates with the loop of wire just as the slip rings do with the rotor

of an 5) generator. ?ach half of the commutator ring is called a commutator

segment and is insulated from the other half. ?ach end of the rotating loop of wire

is connected to a commutator segment. !wo carbon brushes connected to the

outside circuit rest against the rotating commutator. One brush conducts the current

out of the generator" and the other brush feeds it in. !he commutator is designed so

that" no matter how the current in the loop alternates" the commutator segment

containing the outward#going current is always against the QoutQ brush at the

proper time. !he armature in a large 3) generator has many coils of wire and

commutator segments. (ecause of the commutator" engineers have found it

necessary to have the armature serve as the rotor&the rotating part of an apparatus*

and the field structure as the stator &a stationary portion enclosing rotating parts*.

1hich is the inverse of an 5) Generator.
http://www.k12.nf.ca/gc/scienceweb/physicsweb/Physics3204/studentprojs/Project26/ac_generator.htmhttp://www.k12.nf.ca/gc/scienceweb/physicsweb/Physics3204/studentprojs/Project26/ac_generator.htm


37/47

Type* o' DC $enerator*:

In some 3) generators" the direct current needed for the electromagnets that make

up the field structure comes from an outside source" just as it does in most 5)

generators. !hese 3) generators are called separately e+cited generators. %any

other 3) generators use part of the direct current they produce to operate their own

electromagnets. !hese generators are called self#e+cited generators. 5 self#e+cited

3) generator depends on residual magnetism##that is" a small amount of

magnetism remains in the electromagnets after the generator is shut off. 1ithout

this residual magnetism" it would be impossible to start a self#e+cited generator

once it had stopped.

!he direct current needed for a self#e+cited generatorRs electromagnets can be

drawn from its armature by means of three different connectionsD hunt" eries and

)ompound" a combination of shunt and series connections.

!he type of generator used for a certain task depends on the amount of voltage

control required. 4or e+ample" a 3) generator used to charge a battery needs only

simple voltage control. It might be a shunt generator.

5 3) generator that supplies electricity for a passenger elevator needs more

complicated voltage control. It would be a separately e+cited generator.


38/47

1*e* o' DC $enerator*:

%any 3) generators are driven by 5) motors in combinations called motor#

generator sets. !his is one way of changing alternating current to direct current.

4actories that do electroplating and those that produce aluminum" chlorine" and

some other industrial materials need large amounts of direct current and use 3)

generators. o do locomotives and ships driven by diesel#electric motors. (ecause

commutators are comple+ and costly" many 3) generators are being replaced by

5) generators combined with electronic rectifiers. ;ectifiers are devices that let

current flow in one direction only. !hey permit use of simpler" more rugged 5)

generators" even when 3) is required.

3)#3) )O=:?;!?;

!he %)@C0A@5K? series is a monolithic control circuit delivering themain functions for 3)#3) voltage converting. !he device contains aninternal temperature compensated reference" comparator" duty cycle controlledoscillator with an active current limit circuit" driver and high current output

switch. Output voltage is adjustable through two e+ternal resistors with a ,-reference accuracy. ?mploying a minimum number of e+ternal


39/47

6 1) witch)ollector

, 1? witch?mitter

@ !) !iming)apacitor

C G=3 Ground

2 )II )omparatorInvertingInputA :)) :oltageupply

Ipk Ipkense

/ 3;) :oltage3river)ollector

O)I''5!O;

Sy-9

o&

Para-eter Te*tCondition* "in, Typ, "a%,

1nit

fO)

4requency :pin20: )!6n4 !a,2o) ,C

@@

C,

H$

Ic

)harge)urrernt :))2toC0: !a,2 ) , @ C

Idischg

3ischarge)urrent :))2toC0: !a,2o) 6C0 ,00 ,A0 5

IdischgK

3ischargeto)harge Pin:)) !a

,2o)2., A., .2


40/47

OF!PF! 1I!)H

Sy-9 Para-eter Te*tCondition* "in, Typ, "a% 1nit

:)?&

aturation I165 Pins6"/ 6 6.@ :

:)?&sat*

aturation:oltage I165 ;pin//,to:))"4orcedN,0

0.C2 0. :

h4 3))urrentGain I165 :)?2: !a,2o) 2 6,0

I)&o)ollectorOff#tate)urrent

:)?C0: 0.06 600 5

)O%P5;5!O;

Sy-9 Para-eter Te*tCondition* "in, Typ, "a% 1nit

:th

!hreshold:oltage !a,2o)!a!'O1to!HIGH

6.,,26.,6

6.,2 6.,26.,7

::

;egli !hreshold:oltage :))@toC0: 6 2 m:

II Input(ias)urrent :I=0: #2

#C00 n5

TOTAL DE!ICESy-9 Para-eter Te*tCondition* "in, Typ, "a% 1nit

I))

upply)urrent :))2toC0: )!6n4Pin:)) :pin2S

: Pin,G=3

,.26.2

CC

m5m5

:!5;!#FP

tart#up:oltage&noteC*

!a,2o) )!64 Pin20:for "[email protected]

,.66.2

::


41/47

"0P1CA. APP.1CA"1ON C1RC21"

Step-Up Converter

Step-Down Converter


42/47

!?! )O=3I!IO=

Te Conditi !a&ue 1nit

'ine;egulation :I=62to,2:" IO200m5 2 m:

'oad;egulation :I=,2:" IO20to 200m5 @0

m:

Output;ipple :I=,2:" IO200m5 60

0

m:

?fficency :I=,2:" IO200m5 /0

-

I) :I=,2:" ;'O530.6 6.,

5

Voltage Inverting Converter


43/47

Calculation

Para-eter StepB

1p

StepBDown

/Continuo*!o&ta)eIn+ertin)

tonKtoff :outT:4U:inVminW

: U:

:outT:4

: U: U

X:outXT:4:inU

:&tonYtoff*ma+ 6Kf min

6Kfmin

6Kfmi

)! C.2+60#2ton C.2+60#2ton C.2+60#2ton

IP&switch* ,Iout&ma+*Z&tonKtoff*Y6[

,Iout&ma+

,Iout&ma+*Z&tonKtoff*Y6[

;) 0.@KIP&swit

ch*

0.@KIP&swit

ch*

0.@KIP&swit

ch*)O Ioutton:rippleVpUpW

IPVswitchWVtonTtoffW

U

Ioutton

:rippleVpUpW

'&min* :inVminWU:sattIPVswitchWonVma+:inVminWU:satU:outt Vsw c W

:inVminWU:sattIPVswitchWonVma+W

=O!?D:sataturationvoltageoftheoutputswitch

:4 4owardvoltagedropoftheoutputrectifier!H?4O''O1I=GPO1?;FPP'>)H5;5)!?;I!I)%F!(?)HO?=D :in =ominalinputvoltage:out3esiredoutputvoltage"X:outX6.,2&6Y;,K;6* Iout3esiredoutputcurrentfmin %inimumdesiredoutputswitchingfrequencyattheselectedvaluesof:inandIo:ripple 3esiredpeaktopeakoutputripplevoltage.Inpractice"thecalculaedcapacitorvaluewillandtobeincreasedduetoitsequivalent seriesresistanceandboardlayout.!heripplevoltageshouldbekepttoalowvaluesinceitwilldirectlyaffect thelineandloadregulation.

Step-up With External NPN Switch


44/47

Step-down With External NPN Switch

Step-down With External PNP Switch


45/47

Voltage Inverting With External NPN Switch

Voltage Inverting With External PNP Saturated Switch


46/47

Dual Output Voltage

Higher Output PowerHigher Input Voltage


47/47

CO#CL1SIO#

In order to achieve a growth rate of #/ - as envisaged in =ationalpolicy of India "it is also required to tap all the small Hydro Power

potential of the country. !he encouraging performance shown by the!awa project itself set an e+ample for inviting private investment in the

small Hydro Power Project sector" especially in view of the fact that

'arge Hydro power projects involve huge capital investment and long

gestation period which private partners do not afford to bear. !he

utili$ation of small Hydro Power Potential is especially required in all

states where the utili$ed potential is very low like in %P and therefore

optimum utili$ation of the same may set up an stepping up stone forachieving self sufficiency in power sector in country.

hydro power generation system

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