IAS Mains Electrical Engineering 2004

8/9/2019 IAS Mains Electrical Engineering 2004

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where

X t ~ j

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is

the frequency response oflhe sequence

x(nT), T

is

the sampling period and

X {j 0.) is

the

Fourier transform of t h c - ~

continuoustime waveform. lf

the analog frequency response

is

band

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to the

rangt : 0 i < :r'T wha

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the rww rt>lation

be

:

1

2x(}=l2

(b) (i) Illustrate and compare speedcurrent and

motor

with

thai of series and shunt

motor.

0

(ii}

A 3-phase. 5 Hz, I G poic gencrnror with t

n ~ C t e d windings has 144 slots with 10 conduc

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11/14

compens:.uor that

will

satisfy tlw

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requirement '

1

20

(b) 1\

;>

MYA. kV

,,.,,erwratcH-

with

x

, 20 \,

is

u

conrwded

through

a transformer. line and a transformer

to

:1 hus 1h:n s u p p l i f ~ s three i d t ~ n t i c a l motors as shown

in

fig. hdow. Each motor

has

x ~ ~ 2:) \, and xci

30

h, on

a l ~ ~ t . , r :

o f ~

MVA.

G.G kV.

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s t ~ p up 1ransforrm-r is .5

\1VA.

ll'GG kV with a l e ; t k a g < ~

n ~ < ~ c : u n c r : ~ of

o ~ ~ _ < H l ( ~ t h ~ ~ ~ of the step-down ; r a n s i o r m ~ r

ts ?:>

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hu:;

l ' ( l l t a g ( ~ at

t h f ~

rnoto '

is G. ) I


12/14

h1brication of a

monolithic circuit

sh )w.n below :

2


13/14

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ore

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.

20

;t..flf

Documents

IAS Mains Electrical Engineering 2004