nttf question bank

8/16/2019 nttf question bank

1/57

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


2/57

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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4/57

, 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


5/57

; . 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


6/57

@.( 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


8/57

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


10/57

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


12/57

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


13/57

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 !


14/57

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#!


15/57

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


16/57

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+


17/57


18/57

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


19/57

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


20/57


21/57

hi/her rotor resistance

low rotor resistanceac

dc $& a &tat$#)a!,

$& a ! 6# 6$)+,B

;2BB


22/57


23/57


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!


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29/57

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


30/57

' '.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


31/57


32/57

; 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


33/57

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'.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


34/57

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


35/57


36/57

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


37/57

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


45/57

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


48/57

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


49/57

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


51/57

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'.1

1'.2

1'.'

1( 3 !ER 3!OR1(.11(.21(.'


52/57


53/57

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 inducti&ecircuits


54/57

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 '


55/57

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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