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SEMESTER : II SUBJECT : EL
Chapt ! Na" T#p$% Na"
1 POWER SOURCES
1.1 classification of powersources
1.2 Electrochemical primary and secondary batteries
2 E!WOR" !#EORE$S
2.1 %richoffas laws
2.2 Source con&ersion
2.' super position theorem
2.( !he&enins theorem) ortons theorem
2.*
Chapt!&
S'(T#p$%
Reciprocity theorem)ma+imum power transfer)simple problems
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2., -elta star and star delta transformations
' Electrostatics and capacitance '.1
ma/netism
static electricity)absolute and relati&e permitti&ity)laws of electrostatics)electric field)field stren/th)
electric flu+)ener/y stored in capacitor
0asic defintion of flu+)mmf)reluctance ) andreleation between 0)#)
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, S 4 E P#3SE 3.C.C RCU !S
,.' 3C throu/h R) and C and power factor
,.(
;.1
3C throu/h R)R8C and R8 series and parallelcircuits
4eneration of poly phase &olta/es and phasese6uence
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; . PO < P#3SE 3.C C RCU !S
;.2 Star or wye =y> connection and delta connections
? !ransformer ?.1
@ DC G ) !at#!
@.1 4enerator Principle) Construction A wor%in/
@.2 Parts of a 4enerator
@.' E$5 e6uation of 4enerator
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@.( osses and Efficiencies in -C 4enerators
@.* Characteristics of -C /enerators
1B -C motor
1B.1 $otor Principle) Comparison of motor and /enera
1B.2 0ac% E$5 and olta/e E6uation of a $otor
1B.' !or6ue) 3rmature !or6ue and shaft !or6ue
1B.( Rated Speed and speed re/ulation and sped con
11 $O!OR C#3R3C!ER S! CS
11.1 ! &s la) &s la of 3 -C Shunt and series motor
11.2 ! &s la) &s la of 3 -C Compound motor
12 -UC! O $O!ORS
12.1 Classification of 3C $otors
12.2 Sin/le Phase and !hree Phase nduction $otors
12.' 4eneral Principle A Construction
12.( Startin/ of nduction $otor
12.* Power Sta/es in nduction $otor
12., Relationship between Slip) !or6ue
12.;
1' SPEC 3 PUPOSE $O!ORS
1'.1 Uni&ersal motors and its specialty
1'.2 Stepper $otors and P$-C $otor
Speed control of an nduction $otor
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1'.' ntroduction to ser&o $otors
1( 3 !ER 3!OR
1(.1 0asics Principle A -etails of Construction
1(.2 Stationary 3rmature A Rotor
1(.' Speed and 5re6uency Relation
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PART A
CTRICAL ENGINEERING SUBJECT CODE : CP15 02 04
FILL IN THE BLANKS
*UESTION
31
!he power sorces are classified into two DDDDDD and DDDDDDD
32 !he source which supplies in the form of current is called DDDDDDDDDD source
3'
3(
3 * 3n electric battery consists of a number DDDDDDDDDcells
3, secondary cell is also called asDDDDDDDDDDDDDD
3; 3 /roup of cell is called asDDDDDDDDD
3? !he fuel cell will con&erts DDDDDDDDD into DDDDDDDDDDD
3@ 5uel cells contains two electrodes DDDDDD and DDDDD
3 1 !he two %richoffas laws are DDDDDDDDDDDD and DDDDDDDDDD
3 2
3 '
0 (!he methods used to simplify the circuits is called as DDDDDDDDDDDDDDDDD
0 *
0 ,
0 ;
Cat +#! ,
*'&t$#)N#-
!he source which supplies in the form of the &olta/e is called as DDDDDDDDDDDDDDsource
f the &oltafe across an ideal &olta/e source can be specified independently of any other&ariable in an circuit is calledDDDDD
!he sum of &olta/e rises nmust e6ual to the sum of &olta/e drops is DDDDDDDDDDDDDDlaw
3ll current enterin/ a unction point must e6ual to all current lea&in/ that unction point iscalled as DDDDDDDDDDDDDDDDD
!he method is used to find the solution to networ%s with two or more sources they arenot in series and parallel is called DDDDDDDDDD
!he the&enins theorem is used to find any particular DDDDDDD and DDDDDDDDDD in alinear networ%
!he theorem states that to obtain ma+imum e+ternal power from a surce wityh a finiteinternal resistance is called DDDDDDDDDDD
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C ?
3 1
3 2 !he space around an electrical char/e is DDDDDDDDDD
3 '
3 ( !he amount of electric field passin/ throu/h a surface is called DDDDDDDD
3 * 4enerally an conductin/ medium or insulator is called as DDDDDDDDDDDDD
3 ,
3 ;
3 ? !he unit of permiti&ity is DDDDDDDDDDDD
3 @
3 1B !he wor% of capacitor is toDDDDDDchar/e
31 !he stre/th of ma/ent lies at the ends is called asDDDDDDD
32
3' !he unit of ma/netic flu+ is DDDDDDDDDDDDDDD
3( !he symbol of ma/enic flu+ is DDDDDDDDDDDDD
3* !he force that produces the ma/netic field is called DDDDDDDDDDDD
3, !he unit of $$5 is DDDDDDDDDDDDD
3;
!he two types of transformations to ma%e circuit connection and calulation easier is DDDDDDDDDDDD and DDDDDDDDD
!he study on electric char/es in the static or steady state conditions is called as DDDDDDDDDDDDDD
electric field induced by a posti&e electric char/e in DDDDDDDDD and field induced byne/ati&e electric char/e DDDDDDDDDD
!he material measures the ablity of thar material to withstand &olta/e differnces is called DDDDDDDDDDDDDDD
!he ratio of electric displacement &ector in dielectric medium to the applied electric fieldis called DDDDDDDDDDDDDDDDDDDDDDD
!he force of attraction or repulsion between two point char/es is directly prpotional to theproduct of ma/initude of each char/e and indirectly proportional to the s6uare of
distance between them is called as DDDDDDDDDDDDDDDD
!he /roup of force libes /oim/ from the pole to S pole of a ma/net is called as DDDDDDDDDDDDD
!he opposition to the establishment of a ma/netic iels in a material is called DDDDDDDDDDDD
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3? !he reluctance is denoted byDDDD
3@
!he type of char/e DDDDDDDDDDD and DDDDDDDDDDDDDD in electric field
31B
!he type of char/e in ma/enitic field is DDDDDDD and DDDDDD
311 i%e poles will DDDDDDDD unli%e poles will DDDDDDDDDDD
3
1
3
2
3' nduced e.m.f can be either DDDDDDDDD and DDDDDDDDDDDDDD
3(
3*
f current chan/es in coil1) an emf is induced in coil 2 is called as DDDDDDDDDDDD.
3, !he unit of inductance is DDDDDDDDDDD
3 ; !he inductance is represented by letter DDDDDDDDD
0
?
3 1
0 2
0 ' 3 plus =F> si/n when used in connection with phase difference denotes DDDDDDD
0 ( 3 minus=8> si/n when used in connection with phase difference denotes DDDDDDD
0 * !he current and &olta/e are in phase. !he ma/nitude is RGDDDDDDDD
!he production of a ma/netic field by current in a conductor is called as a DDDDDDDDDDDDDD
!he DDDDDDDD law states that electroma/netically induced current always flows in suchdirection that the action of the ma/netic field set up by it tends to oppose the &ery cause
which produces it.
Conductor remains stationary and flu+ lin%ed with it) is chan/ed is called as DDDDDDDDDDDD
!he cur&e of the flu+ density =0> &ersus the ma/netic force =#> is calledasDDDDDDDDDDDDDDDDDDDD
!he term alternatin/ indicates only that the wa&eform alternates between two prescribedle&els in a set time se6uence is called as DDDDDDDDD
!he an/ular fre6uency w can be thou/ht of as the rate at which the an/le of the sinewa&e chan/es 3t any time GDDDDDDDDDD
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0 , !he current and &olta/e are in phase in a resistor then P GDDDDDDDDD
0 ; HI 7 plays the part of resistance. t is called DDDDDDDDDDDDDDD
0 ? nducti&e reactance is the DDDDDDDDDDDDlimitin/ property of an inductor.
0 @ !he inducti&e reactance symbol is DDDDDDDDDDDDD
0 1Bn 3C pure inducatance the Current DDDDDDD behind &olta/e by @BJ
0 11 3c throu/h pure capacitor Current DDDDDDD &olta/e by @BJ.
0 12K c is %nown as DDDDDDDDDD
0 1' Unit of C is DDDDDDDDD
C 1( 3n R circuit has DDDDDDDDDD and DDDDDDDDDDD
C 1*
C 1,
C 1; !he resonace is K GDDDDDDDDDDDDD
C 1? n R C c%t the resonance is DDDDDDDDDDDDDDD
C 1@!he resisitor is a DDDDDDDDDDD component
C 2B!he power due to inducti&e or capacitance reactance DDDDDDDD
C 21 !he comibination of real power and reacti&e power isDDDDDDDD
C 22
!he ratio between actual power to the apparent power is called asDDDDDDDDDDD
3 1 !he three phase si/nals has phase sift of DDDDDDDD
3 2t is order in which the three phase attain their ma+imum &alue is called as DDDDDDDDD
3 ' !he similar ends of three coils are oined to/ether at point DDDDDDDDDDD
n 3C throu/h RC series circuit Ө= ________
n a parallel RC circuit) the admittance phasor is the sum of the DDDDDDDDDDDD and DDDDDDDDDD susceptance
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3 ( !he wire connected to DDDDDDDDDDDDDDDDD
3 * !he potential difference between any line and neutral point /i&es the DDDDDDDDDDDD
3 , !he potential difference between any two line /i&es the DDDDDDDDDDDDD
3 ;n a wye system) the DDDDDDDDDD current is e6ual to the DDDDDDDDDDD current.
3 ? !he dissimilar ends of three phase windin/s are oined to/ether DDDDDDDDDDD
3 @n a delta system) the line current is DDDDDDDD than the phase current
3 1B n delta connection the phase &olta/e is e6ual to DDDDDDD
3 1
3 2 !ransformer is rated in DDDDDDDDDDDDDDDDDDDDD.
3 ' olta/e transformation ratio of a transformer is G DDDDDDDDDD.
3 ( !ransformer transfers power without chan/in/ of 888888888888888888888
3 * 3 transformer transforms both DDDDDDD and DDDDDDD.
3 , Short circuit test of transformer determinesDDDDDDDDDDD.
3 ; Potential transformers are used to measure DDDDDDDDDDD.
3 ? Eddy current loss can be minimi9ed by DDDDDDD
3
1
Th a!"at'! #. a /% "a%h$) $& a"$)at / t# ! /'%
2
I) a /-%- + ) !at#! th + ) !at / ". $& /$! %t , p!#p#!t$#)a t# th
3
'Th (!'&h & .#! %#""'tat$#) a! "a/ #.
(
Th ,# #. a DC "a%h$) $& "a/ #.
3
*
Th ". p!#/'% / $) a /% + ) !at#! $& 3333333 $)/'% / ".
,
Th ". 'at$#) #. DC + ) !at#! $& 333
!ransformer wor%s on theprinciple of DDDDDD of two coils
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0 ;
h$%h #&& & #%%'!!$)+ $) a /% "a%h$) 6a!$ & &$+)$.$%a)t , 7$th #a/8
C ?
Th #p ) %$!%'$t %ha!a%t !$&t$%& #. a /% + ) !at#! $& th %'!6 ( t7 )
3 1
A DC "#t#! $& '& / t# 333333333333
3
2
!he &alue of bac% emf in a -C motor is ma+imum at DDDDDDDDD
9
Th %#)/$t$#) .#! "a $"'" ..$%$ )%, $) a DC "#t#! $& "a $"'" $& 333333333;
0
4
I) a /% "#t#! ')$/$! %t$#)a t#! ' $& p!#/'% / 7$th th h p #.
5
!he tor6ue which is a&ailable at the motor shaft for doin/ useful wor% is %nown as DDDDDD
C <
!he speed at which the rotatin/ ma/netic field produced by stator currents rotates in an in
C 1
Th Ta=Ia +!aph #. a /% & !$ & "#t#! $& a
C 2
!he electrical characteristic of a dc motor is the cur&e between
C 1
A &$)+ pha& $)/'%t$#) "#t#! $&
0 2
Th p!$)%$p #. #p !at$#) #. a th! pha& $)/'%t$#) "#t#! $& "#&t &$"$ a! t# that #
3
'
Rotatin/ ma/netic field is produced in an induction motor because of
(
Sp / #. a & '$!! %a+ $)/'%t$#) "#t#! %a) ( %#)t!# / .!#"
3 *
Th a/6a)ta+ #. th! pha& $)/'%t$#) "#t#! #6 ! &,)%h!#)#'& "#t#! $&
C ,
!he mechanical power a&ailable in the rotor output produce DDDD
C ;
!he difference between the synchronous speed and actual speed of a motor is DDDDD
3 ?Star8delta startin/ method is only applicable to DDDDD motor.
3 1
S$)+ pha& ')$6 !&a "#t#! %a) ( '& / #)
0
2
A &t pp ! "#t#! $& a 33333333 / 6$%
'
A &t pp ! "#t#! "a, ( %#)&$/ ! / a& a 3333333 %#)6 !t !
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0 (
!he most common two8phase ac ser&omotor differs from the standard ac induction motor
0 1
!he alternator /enerates
0 2
0 '
Th .! ' )%, #. 6# ta+ + ) !at / (, a) a t !)at#! ha6$)+ 4 p# & a)/ !#tat$)+ at
Th a!"at'! #. a) a t !)at#!
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ANS ER RONG ANS ER
current&olta/e
&olta/ecurrent
ndependent &olta/e sourceindependent current source
electrochemical electrodes
rechar/eable cellnon rechar/eable
battery-C source
electrical ener/y to chemical ener/y
anode and cathodehydro/en and o+y/en
faradays laws and len9 law
%richoffas &olta/e law%richoffas current law
%richoffas current law%richoffas &olta/e law
source con&ersionssource transformations
super position theoremnortons theorem
&olta/e and currentresistance and current
ma+imum power transfer super position theorem
current source and &olta/esource controlled &olta/e source and
controlled current source
chemical ener/y into electricalener/y
%richoffas &olat/e law and%richoffas current law
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delta star and star deltadelta delta and star star
static electricity
electric field
electric field ma/netic field
left and ri/ht
ri/ht and left
electric flu+ma/netic flu+
dielectric electricity
dielectric sten/thpermiti&ity
permitti&itydielectric
farad meter meter farad
coulombs law
faradays laws
storeoppose
polesn pole
ma/netic flu+electric flu+
weber electric flu+
L Ө
$$5 weber
ampere weber
reluctance flu+
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rms N rms R
inducti&e reactance inducti&e resistance
current &olta/e
K KC
la/s leads
leads la/s
capaciti&e reactance. capacitance
farad henry
resistor)inductor capacitor)resistor
sinwt
conductance)capaciti&e reactance)inductance
KC ss
9ero unity
acti&e reacti&e
reacti&e power acti&e power
apparent power reacti&e power
power factor acti&e power
phase se6uence phase differnece
star connection delta connection
tan81=Kc R>
12B @B
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netural wire phase
phase &olta/e line &olta/e
line &olta/e phase &olta/e
line)phase phase &olta/e
delta connection star connection
hi/her lower
line &olta/e line current
mutual induction Self inductance
"3 3
E1/E2=I2/I1=K E2/E1=I1/I2=K
5re6uency &olta/e
&olta/e and current
copper loss iron loss
&olta/e current
aminatin/ the core eddy current loss
%#pp ! #&&)'"( ! #. p# &
F! ' )%,
carbona '"$)$'"
cast iron
a '"$)$'"-ynamically induced emf
&tat$%a , $)/'% / ". E/G F aRa
E/G 8 aRa
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hi/her rotor resistance
low rotor resistanceac
dc $& a &tat$#)a!,
$& a ! 6# 6$)+,B
;2BB
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!
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Chapt ! Na" T#p$% Na"
1 POWER SOURCES
1.1 Classification of Power sources
1.2
2 E!WO" !#EORE$S
2.1
2.2
2.'
2.(
2.*
Chapt!&
S'(T#p$%
E EC!RO C#E$ C3 PR $3R< 3 -SECO -3R< 03!!ER ES
"irchhoff7s laws) &olta/e sources andcurrent sources.
Source con&ersion) simple problems insource con&ersion
Superposition theorem) simple problemsin super position theorem
!he&enin7s theorem) orton7s theorem)simple problems
Reciprocity theorem) $a+imum powertransfer theorem) simple problems
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' '.1
( $a/netism (.1
*
*.1
*.2
E EC!ROS!3! CS 3 -C3P3C !3 CE
Static electricity) absolute and relati&epermitti&ity of a medium) laws of
Electrostatics ) electric field) field stren/th)electric flu+ density) ener/y stored in a
capacitor.
E EC!RO$34E! S$ 3 --UC! O
Relation between ma/netism andelectricity) production of induced e.m.f andcurrent and 5araday7s laws of
electroma/netic induction
-irection of induced e.m.f and current8en97s law:self inductance and mutualinductance
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; PO< P#3SE 3.C C RCU !S
;.2
? !ransformer
@ -C 4E ER3!ORS
@.14enerator Principle) Construction A wor%in
@.2 Parts of a 4enerator
@.' E$5 e6uation of 4enerator
@.( osses and Efficiencies in -C 4enerators
@.* Characteristics of -C /enerators
1B -C $O!ORS
1B.1 $otor Principle) Comparison of motor and1B.2 0ac% E$5 and olta/e E6uation of a $otor
1B.' !or6ue) 3rmature !or6ue and shaft !or6ue1B.( Rated Speed and speed re/ulation and sp
11 $O!OR C#3R3C!ER S! CS
11.1
11.2 ! &s la) &s la of 3 -C Compound motor
12.1 Classification of 3C $otors
Star or wye =y> connection and deltaconnections
! &s la) &s la of 3 -C Shunt and seriesmotor
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12 -UC! O $O!ORS
12.2 Sin/le Phase and !hree Phase nduction $
12.( Startin/ of nduction $otor
12.* Power Sta/es in nduction $otor
12., Relationship between Slip) !or6ue
12.;
1' SPEC 3 PUPOSE $O!ORS
1'.1Uni&ersal motors and its specialty
1'.2 Stepper $otors and P$-C $otor
1'.' ntroduction to ser&o $otors
1( 3 !ER 3!OR
1(.1
1(.2 Stationary 3rmature A Rotor
1(.' Speed and 5re6uency Relation
Speed control of an nduction $otor
0asics Principle A -etails of Construction
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PART A
SEMESTER : II SUBJECT : ELECTRICAL ENGINEERING SUBJECT CODE : CP15 02 0
CHOOSE THE CORRECT ANS ER
Cat +#!, *' &t$#)& A
3
1
power source is classified into two types DDDDDDDDDD
2 !he source which supplies in the form of a current is DDDDDDDD &olta/e source
' &olta/e source
(
3
* 3n electric battery consists of a number of DDDDDDDD
dc source
, !he battery con&erts chemical ener/y into DDDDDD li/ht ener/y
; !he battery uses DDDDDDD source 3C? mercury cell is e+ample of DDDDDDD battery secondary
@Secondary battery are DDDDDDDDD
1B 5uel cells uses DDDDDDDDDD fuel
11 !he positi&e side of fuel cell is DDDDDDDD cathode
3
1 !he two %richoffas laws are DDDDD "C
2 3round any complete loop) the sum of the &olta/e rises must e6 "C
' 3ll current enterin/ a unction point must e6ual all current lea& "C
0 ( bilateral
0 * !he theorem used to find the solution to networ%s with two or monortonMs
0 , the&enins
0; !o obtain ma+imum e+ternal power from a source with a finite the&enins
*' &t$#)N#-
current sourceand &olta/esource
!he source which supplies in the form of a &olta/e is DDDDDDDDDD
f the &olta/e across an ideal &olta/e source can be specifiedindependently of any other &ariable in a circuit. t is called an
DDDDDDDDDD
independentcurrent source
nonrechar/eable
hydro/en Ao+y/en
!he double arrow indicate that the transformation is DDDDDDDDDD
!he specific portion of a networ% by replacin/ the remainin/networ% with an e6ui&alent circuit DDDDDDDDD
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0? f current chan/es in coil 1) an emf is induced in coil 2.
mutal inductance
0
@
field stre/th
3 1 !he wa&eform alternates between two prescribed le&els in a se -C &olta/e
32
&olta/e
0 ' 3 plus =F> si/n when used in connection with phase difference la/( a minus=8> si/n denotes DDDDDDDDDDD la/
0*
RG R, !he power PG DDDDDDDDDDDD rmsN rms
0 ; HI 7 represents DDDDDDDDDDDDDDDDD 0 ? !he inducti&e reactance symbol is DDDD KC0 @ la/s0 1B DDDDDDDDis %nown as capaciti&e reactance K0 11 unit of C is DDDDDDDDDDDDD ohms
0 12 conductance
0 1' !he phase an/le is denoted as DDDDDD
0 1( f K GKC the circuit is called as DDDDDDDDDD
0 1* R C c%t is in resonance Circuit impedance is DDDDDDDDDD ma+imum
0 1B fre6uencey
C11 Which of this is a 3cti&e component DDDDDD inductor
C 12 Which of this is a Reacti&e component DDDDDDDDDD inductor
C 1' Power which is actually dissipated in the circuit resistance PG
C1( !he acti&e power e6uation is DDDDDDDDDDD Cos watts.
C 1* !he reacti&e power is denoted by DDDDDDD P
C 1, acti&e power
C1; 3R is meant for DDDDDDD
C 1? Product is neither the real power nor the reacti&e power) but a acti&e power C 1@ !he apparent power is denoted by DDDDD R
C 2B acti&e power
C21 5or a purely resisti&e load the power factor is DDDDDD la/
3 1 n a three phase si/nal the phase shift is DDDDDDD
!he cur&e of the flu+ density =0> &ersus the ma/netic force =#>is called DDDDDDDDDDDDD
3 leadin/ alternatin/ 6uantity is one which reaches its ma+imumor 9ero &alue earlier as compared to the other 6uantityDDDDDDD
!he simplest case is a resistor in a circuit. !he current and&olta/e are inphase. !he ma/nitude is DDDDDD
inducti&eresistance
3C throu/h pure capacitor current DDD by @B
!he sum of the conductance and capaciti&e susceptancephasors is called DDDDDDDDDDDD
inducti&eresistance
f r is meant for DDDDDDDD
the power due to inducti&e or capacitance reactance of thecircuit is called DDDDDDDDDDDD
&olt amperereacti&e
!he ratio between actual power to the apparent power is called DDDDDDDDDDD
@B
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3 2 delta star
3 ' !he star to star connection is called as DDDD
3 ( &olta/e
3 * &olta/e 3 , n a star connection system line GDDDDDDDDDDD &olta/e
3 ; delta star
3 ? n a delta system) the line current is e6ual to the DDDDDDDDDD phase curent
3 1 !ransformer wor%s on the principle of 5lemin/s left han
3 2 3 !ransformer transforms DDDDDDDDD
fre6uency
3 ' !ransformer cores are laminated in order to increase power
3 ( !he E$5 e6uation of transformer is (.((f
3 * 5re6uency
3 1 5lemin/7s ri/ht hand rule is applicable to dc /enerator
32 Th p'!p#& #. a %#""'tat#! $) a /% + ) !at#! $& t#
' !he yo%e of a -C machine is made up of DDDDDDD Silicon steel
3( Th %#"" !%$a ..$%$ )%, #. a &h')t + ) !at#! $& "a $"'" %#)&ta)t
* Th ! at$#)&h$p ( t7 ) + ) !at / ". a)/ app $ / 6# ta+ E+ > ? @ IaRa
0 , Stray losses consist of DDDDDDDDDDDD
C; ? a)/ Ia
? Th #p ) %$!%'$t %ha!a%t !$&t$%& #. a /% + ) !at#! $& th %'! ? a)/ Ia@ Th t !)a %ha!a%t !$&t$% #. a /% + ) !at#! $& th %'!6 ( ? a)/ IL
3 1 A /% "#t#! %a) ( ## / 'p#) a& /% + ) !at#! 7$th th p# reduced 3
2 Th $)/'% / ". #. a!"at'! %#)/'%t#!& #. a /% "#t#! $& sinusoidal' Th %'!! )t /!a7) (, a 120? /% "#t#! #. a!"at'! ! &$&ta)% 2B
0 ( Th &ha.t t#! ' $) a DC "#t#! $& && tha) th t#ta a!"at' copper losss
0 * Th &p / #. a DC "#t#! $& 333333333 GEb
C 1 Th Ta=Ia +!aph #. a /% & !$ & "#t#! $& a
C 2 Th %t!$%a %ha!a%t !$&t$% #. a /% "#t#! $& th %'!6 ( t7
C 1 Which of these types of motor is self startin/Q dc motor
!he similar ends of three coils are oined to/ether at point iscalled DDDDDDDD
'phase ( wiresystem
!he potential difference between any line and neutral point/i&es the DDDDDDDDDDD 0ut the potential difference between any two line /i&es the
DDDDDDDDDDD
!he dissimilar ends of three phase windin/s are oined to/etheris called DDDDDDDDDDD
!ransformer is a static piece which transforms electric powerfrom one circuit to another without chan/in/
$)%! a& #'tp'
ma/ne c anmechanical
!he internal characteristic of a dc /enerator is the cur&ebetween
parabola fromno load too&erload
tor6ue andarmature current
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02 Th#& $)/'%t$#) "#t#!& 7h$%h "p #, & '$!! %a+ !#t#!&
'
3 ( Th &p / at 7h$%h th ! 6# 6$)+ . ' !#tat & $& %a / 3333
C * !he mechanical power a&ailable in the shaft produce DDDD rotor tor6ue
C , Th & $p #. a) $)/'%t$#) "#t#! $& +$6 ) a&
3 ; series motor
3 1 h$%h "#t#! $& "#&t &'$ta( .#! 6a%''" % a) !&8 uni&ersal motor
0
2 Th !#t#! #. th &t pp ! "#t#! ha& )# windin/s
' A &t pp ! "#t#! $& a 33333333 / 6$% pneumatic
0 ( O) #. th (a&$% ! '$! " )t& #. a & !6#"#t#! $& that $t "' loads
0 1 5lemin/Ms left hand rule may be applied to an electric /enerator t direction of rotor r
0 2 n alternator) the rotary part is armature.
0 ' Th .! ' )%, #. 6# ta+ + ) !at / $) a) a t !)at#! / p )/ )'"( ! #. p#
S6uirrel ca/emotor
Pha& 7#')/ "#t#!& $& a %a / a& S6uirrel ca/emotor synchronousspeed
= 8 s> s
rotorresistance startin/ method is only applicable to DDDDDmotor.
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Slip rin/ motor
Slip rin/ motor
rotor speed stator speed none of the abo&e
shaft tor6ue /ross tor6ue none of the abo&e
= s8 >
s6uirrel ca/e motor slip rin/ motor shunt motor
repulsion motor hysteresis motor reluctance motor
brushes all of the abo&e
h,/!a' $% none of the abo&e
fre6uencies speeds &olta/es.
polarity of induced emf direction of induceddirection of ma/netic field.
core. ma/netic field pole none of these.
speed of alternator both =a> and =b> type of windin/
nduction motor none of theabo&e
nduction motor none of theabo&e
= s : > s = : s>
commutator
electromechanical
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A)&7 !&
current source and &olta/e source
current source
&olta/e source
independent &olta/e source.
electrochemical cells
electrical ener/y
-Cprimary cell
rechar/eable
hydro/en A o+y/en
anode
both 3 and 0
"
"C
bilateral
super position
the&enins
ma+imum power transfer
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static electricityelectric field
electric flu+
dielectric
dielectric stre/nth
premitit&ityfarad meter char/ecoloumbs lawstore
poles
ma/netic flu+weber
$$5ampere
reluctanceSE0
north and south poles
electroma/etism
electroma/etism
len9 law
self induced E$5
statically and mutually
henry
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star star
'phase ( wire system
phase &olta/e
line &olta/ephase
delta
phase curent
mutal inductance
both &olta/e and current
minimi9e eddy current
(.((f
5re6uency
dc /enerator
%#)6 !t th $)/'% / a% $)t# /%
cast steel
%#)&ta)t
E+ > ? @ IaRa
ma/netic and mechanical losses
E and a
EB and f ? a)/ IL
re&ersedsinusoidal2B
iron and friction losses
GEb
tor6ue and armature current
' phase induction motor
parabola at li/ht loads and astrai/ht line at o&er loads
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S6uirrel ca/e motor
Slip rin/ motor
synchronous speed
shaft tor6ue
slip rin/ motor
uni&ersal motor
all of the abo&e
speeds
direction of induced emf
ma/netic field poles.
both =a> and =b>
= s : > s
electromechanical
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S
Chapt ! Na" S'( T#p$%
1 POWER SOURCES
1.1
1.2
2 E!WO" !#EORE$S
2.1
2.2
2.'
2.(
2.*
2.,
' '.1
Chapt ! &
E EC!ROS!3! CS 3 -C3P3C !3 CE
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( $34 E! S$ (.1
*
*.1
*.2
, SINGLE PHASE A-C-CIRCUITS ,.1
; POLY PHASE A.C CIRCUITS
;.1
;.2
?
TRANSFORMERS
?.1
DC GENERATORS
@.1
@.2
@.'
@.(
@.*
1B.1
E EC!RO$34E! S$ 3 -
-UC! O
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1B DC MOTORS1B.2
1B.'1B.(
11 $O!OR C#3R3C!ER S! CS11.1
11.2
12 -UC! O $O!ORS
12.1
12.2
12.'
12.(
12.*12.,12.;
1' SPEC 3 PUPOSE $O!ORS
1'.1
1'.2
1'.'
1( 3 !ER 3!OR1(.11(.21(.'
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A ;A ?A @A 1A 2A 'A (A *A ,A ;A ?A @
A1
A 2
A 'A (
A*
G ) !at$#) #. a t !)at$)+ 6# ta+ a)/ %'!! )t
B 1
B 2C 'C (
4eneration of poly phase &olta/es and phase se6uence 1
Star or wye =y> connection and delta connections
2
'(*
A 1A 2A 'A (A *A ,A ;
4enerator Principle) Construction A wor%in/ 312
Parts of a 4enerator 3'(
E$5 e6uation of 4enerator 3 *
osses and Efficiencies in -C 4enerators 0,;
Characteristics of -C /enerators C ?$otor Principle) Comparison of motor and /enerator principle 3 1
Relation between ma/netism and electricity) production ofinduced e.m.f and current and 5araday7s laws of
electroma/netic induction
$a/netic hysteresis) residual ma/netism) ener/y stored inma/netic field8 Rise and decay of current in inductiêuits
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0ac% E$5 and olta/e E6uation of a $otor 32'
!or6ue) 3rmature !or6ue and shaft !or6ue 0 (Rated Speed and speed re/ulation and sped control of -.C. C *
! &s la) &s la of 3 -C Shunt and series motor C 1
! &s la) &s la of 3 -C Compound motor C 2Classification of 3C $otors C 1
Sin/le Phase and !hree Phase nduction $otors 0 2
4eneral Principle A Construction 3
'
(*,;?@
Startin/ of nduction $otor 31B11
Power Sta/es in nduction $otor C 12Relationship between Slip) !or6ue C 1'Speed control of an nduction $otor 3 1(Uni&ersal motors and its specialty 3 1
Stepper $otors and P$-C $otor 02'
ntroduction to ser&o $otors 0 (0asics Principle A -etails of Construction 0 1Stationary 3rmature A Rotor 0 2Speed and 5re6uency Relation 0 '
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E : CP15 02 04
A *' &t$#)& B A)&7 !&
power source &olta/e A current source
battery -C source
primary cell eclanche cell
secondary cell lead acid cell
non8rechar/eable cell. primary cell
rechar/eable cell. secondary cell
5uel Cells 5low 0atteries
3nodePositi&ely char/ed side
Cathodene/ati&ely char/ed side
power watts
"irchoff7s law " A "C
R F e.m.f G B "
ncomin/G out/oin/ "C
load resistor
branch current super position theorem
R!h and E!h Thevenin’s theorem
ma+imum e+ternal power!hT&enin resistance RL=RTH
ty es o! tr"ns!orm"tion
electric char/es in the static st"ti# e$e#tri#ity
electric field e$e#tri# #h"r%e
electric lines of force E EC!R C 5 UK
non8conductin/ medium or insulator &ie$e#tri#
withstand &olta/e differences &ie$e#tri# stre%th Permitti&ity
R
'"(im)m o*er tr"ns!ertheorem
+e$t",st"r "n& st"r,&e$t"tr"ns!orm"tion
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electric field stren/th -#" "#itor store #h"r%e. #h"r%enorth "n& so)th o$e m"%entma/netic flu+) L )nit o! m"%neti# /)( *e erma/neto moti&e force 5m G unit of $$5 3mpere=3>.Opposition of ma/netic field re$)#t"n#ere$)#t"n#e- e$e#tri# e$&B m"%neti# e$&
e$e#trom"%etismL in&)#t"n#e
in&)#t"n#e henrytwo nei/hborin/ coils m)t)"$ in&)#t"n#e
B vs H hystersis #)rve
inductive reactance henrycapacitive reactance !"r"&Reactive power VAR" "rent o*er 3A
Three h"se "n%$es 120
4 net)r"$ *iretr"ns!ormer m)t)"$ in&)#tionst"r to st"r #onne#tion three h"se 5 *ire system$ine #)rrent= h"se #)rrent &e$t" #onne#tion
Tr"ns!ormer 3Ate ) tr"ns!ormer N2 > N1te &o*n Tr"ns!ormer N2 < N1C)rrent Tr"ns!ormer 'e"s)rement o! hi%h #)rrent7otenti"$ tr"ns!ormer 'e"s)rement o! hi%h vo$t"%e
o en #ir#)it test #ore $ossshort #ir#)it test #o er $oss-C /enerator dynamically induced-C /enerator 5lemin/Ms ri/ht #and Rule0rush carbonrotatin/ part armature-C /enerator E/G F aRaconstant loss stray lossStray loss mechanical A ma/netic lossesnternal characteristics E A a-C motor -C supply
ma/netic field by current in aconductor
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