Switchyard Equipment

7/25/2019 Switchyard Equipment

1/73

Introduction to Switchyard

EquipmentAbhishek Kr. Jha

Sr. Engineer


2/73

Switchyard Equipment

LA

CV

C Iso!ator

Circuit "reaker

rans#ormer and $eactor


3/73

Substation %

Assemb!age o# switchyard eqpmt.&busbars& trans#ormers and reactors &au'i!iaries etc.

Incomer and outcomer based on the#ormu!a (

)*VS+V$,-/+sin 0


4/73

INSULATION COORDINATION

Se!ection o# the die!ectric strength o#equipment in re!ation to theoperating 1o!tages and o1er1o!tage2swhich can appear on the system #orwhich the equipment is intended andtaking into account the ser1ice

en1ironment and the characteristicso# the a1ai!ab!e pre1enting andprotecti1e de1ices


5/73

LI345I53 A$$ES6$


6/73

T e m p o r a r y O v e r - v o lt a g e s S w i t c h i n g O v e r - v o l t a g e s O v e r - v o l t a g e s d u e t o l i g h t n i n g .

P o w e r S y s t e m s O v e r v o l t a g e s


7/73

Temporary Over-Voltages

Typically due to faults

!"# pu

ms to te$s of seco$d or eve$ mi$utes

Not da$gerous to i$sulatio$


8/73

S%itc&i$g Over-Voltages

Due to system s%itc&i$goperatio$s

!"' pu ( ' pu depe$ds o$ systemvoltage

mostly damped asymmetricsi$usoids

fro$t time of )rst pea* ( te$s ofs to a fe% ms"

decides e+ter$al i$sulatio$ i$,V.UV system


9/73

Over-Voltages due toLig&t$i$g

Due to /direct0 or /i$direct0 lig&t$i$gstro*es"

*$o%$ to co$tri1ute to '23 of systemoutages i$ ,V 4 UV systems

fe% &u$dred *V to several te$s of 5V" 6e% *A to 722 *A

very s&ort duratio$ 8 times to fro$t 8 ! tofe% te$s of s

times to tail 8 fe% te$s to &u$dreds of s" Decides li$e i$sulatio$ 9:IL;

Severely i$


10/73


11/73

Ad1antages o# 76SA

Impro1ed re!iabi!ity due to simp!icity o# thedesign.

Superior protecti1e characteristics.

7inimum energy absorptioncommensurate with the protecti1e !e1e!spro1ided.

Superior per#ormance on !ow impedancecircuits*e.g cab!e and capacitorapp!ication,

3ent!e operation due to absence o# spark

gaps


12/73

The Zinc Oxide Arresters are made by mixing

ZnO with small amounts of additives such as

Bi2O3, CoO, Cr2O3, nO and !b2O3

"ranuling the mixture, then drying, #ressing

into discs and finally sintering

!3 TIRD AR5ONIC IN S=ST,5VOLTA>, 5A= INTRODUC, ,RRORU?TO !223 IN T, 5,ASUR,DVALU,


13/73


14/73


15/73

CTION O6 RATIN>S O6

CONTINOUS VOLTA>, RATIN>

T,5?ORAR= OV,R VOLTA>,

LI>TIN> OV,R VOLTA>,

S@ITCIN> OV,R VOLTA>,

,N,R>= ANDLIN> CA?ACIT=

89


16/73

Co$ti$uous Voltage rati$g8 - Arrester ca$ operate%it&out a$y type of restrictio$

At present& :;:kV has been speci


17/73

Temporary Over Voltages8 - Capa1ility of Arrester toDeal %it& temporary over voltage of system

At present& :?;kV has been speci8*=, and a!so as per IEEE@C=.@@@& 61erVo!tages upto 8.9 p.u. ha1e been speci


18/73

8

S.5 Characteristics Va!ue*#or D;; kV

System,8 $ated arrester 1o!tage :: kV

= 5omina! Fischarge current*-=; G Sec wa1e,

=; kA

: 7inimum discharge capabi!ity 8= kJ-kV

D Continues operating 1o!tage =>9 7in Switching surge residua! 1o!tage *=

kA,>; kVp

7a' residua! 1o!tage at

i, 8;kA nomina! discharge current ;; kVp

ii, =; kA nomina! discharge current 9; kVp

iii, Steep #ronted wa1e residua! 1o!tage ?=9 kVp

> Hressure re!ie# c!ass D;-9;-: kA*asapp!icab!e,

@ RATIN>S O6 #22 *V


19/73

CV


20/73


21/73

Capacitor voltage transformer

A voltage transformer com#rising a ca#acitor

divider unit and an electromagnetic unit so

designed and interconnected that the secondary

voltage of the electromagnetic unit is

substantially #ro#ortional to the #rimary

voltage, and differs in #hase from it by an anglewhich is a##roximately $ero for an a##ro#riate

direction of the connections


22/73

EMU

H Terminal

Upper !apacitor Unit

"ellow#evel $ndicator

Sec.

Terminal

"o%

#ower !apacitor

Unit


23/73


24/73

There are a##roximately 2%& ' 3(& elements

in

C( about () * 2) elements in C2

+ +oltage Ta# +s- C(./C(0C21

where, +s ' rimary +oltage


25/73

n the event of an element failure in C2, Ca#acitance C2 increases4 5ence, Ca#acitor 6ivider 7atio ncreases4

+ Ta# . ntermediate +oltage 7educes4

5ence !econdary +oltage 7educes4

n the event of an element failure in C( , Ca#acitance C( increases4 Ca#acitor 6ivider 7atio 7educes4

+ Ta# . ntermediate +oltage ncreases4

5ence !econdary +oltage ncreases4

8umber of C2 9lements are lesser , e4g4 2& : hence change in C2 due toone element failure is /(.2&1 x (&& );4

8umber of C( 9lements are more e4g4


26/73

Electromagnetic UnitThe com#onent of a ca#acitor voltage transformer,

connected across the intermediate terminal and the earthterminal of the ca#acitor divider which su##lies the

secondary voltage4 An electromagnetic unit com#rises

essentially a transformer to reduce the intermediate

voltage to the re>uired value to secondary voltage, and aninductive reactance, a##roximately e>ual, at rated

fre>uency, to the ca#acitive reactance of the two #arts of

the divider connected in #arallel4


27/73

Com#ensating 7eactor is #rovided to

com#ensate for the #hase dis#lacement in

Ca#acitor elements

w? (.w /c(0c21

? (. w2/c(0c21


28/73

@erro resonance in C+Ts is due to the

Ca#acitance in +oltage 6ivider in series with

the inductance of the Transformer and series

reactor4 This circuit is brought to resonance byvarious disturbances in the networ that may

saturate the iron core of the transformer, over

heat electro magnetic unit and lead toinsulation breadown4


29/73


30/73

erro resonance in CVs is due to the Capacitance in Vo!tageFi1ider in series with the inductance o# the rans#ormer andseries reactor. his circuit is brought to resonance by 1arious

disturbances in the network that may saturate the iron core o#the trans#ormer& o1er heat e!ectro magnetic unit and !ead toinsu!ation breakdown.

@erro resonance su##ression circuit is #rovided in C+T !econdary to su##ress

@erro resonance oscillations4

The ferro*resonance su##ression device /@!61 contains a saturable reactor, whichacts lie a switch, #resenting a very high im#edance under normal conditions and

switching on a dam#ing resistor across the secondary at a #rescribed voltage, and

switching off the dam#ing load when voltage has normali$ed4 The voltage

sensitive switching strategy effectively su##resses ferroresonance without

im#osing a heavy #ermanently connected stabili$ing burden on the unit4


31/73

Current rans#ormer

As per IEC ;;DD@8

@unctions 4* etering 4

* onitoring 4

* 7elaying.rotection


32/73

Live Ta$* CTs


33/73

Dead ta$* CTs

Hairpin design and Eye Bolt design


34/73


35/73

ech Harameters

E'tended Current $ating( I# C has an e'tended current rating& in percentage

o# the rated primary current& it sha!! be treated as$ated continuous therma! current. *8=;,

$ated Short time therma! current( $7S1a!ue o# the primary current& which a C wi!!

withstand #or one second& without suering harms&the secondary winding being short@circuited.

D;kA #or 8 sec.


36/73

$ated dynamic current( Heak 1a!ue o# the primary current& which a

C wi!! withstand& without suering harms&

the secondary winding being short@circuited. n!ess speci


37/73

"urden( It is the impedance o# the secondary circuit in ohms and

p#.

$ated output( he 1a!ue o# apparent power *in VA at speci


38/73

echnica! Harameters

Accuracy C!ass #or 7easuring Cs(4ighest permissib!e percentage current error atrated current prescribed #or concerned accuracyc!ass.

Standard c!asses@ ;.8& ;.=& ;.9& 8& :& 9or =9 to 8;; o# rated burden

Accuracy c!ass #or Hrotecti1e C(4ighest permissib!e percentage composite errorat rated accuracy !imit primary currentprescribed#or concerned accuracy c!ass.

9H=;& !omposite Error

Protection !lass'#(


39/73

$ated Instrument Limit Hrimary Current(or measuring Cs& the minimum primary current atwhich the composite error N 8;& secondary burdenbeing equa! to rated burden.

Instrument Security actor *IS,(IS rated IHL - rated primary currentSecondary apparatus sa#ety is greatest when the 1a!ue o#IS is sma!!.


40/73

Composite Error(nder steady@state& the rms 1a!ue o# dierencebetween(a, Instantaneous 1a!ue o# primary current& ip.

b, Instantaneous 1a!ue o# secondary current ' rated

trans#ormation ratio& Kn' is

Oc *8;;-Ip,' P*8-,'Q;*ip@Knis,=dtCurrent error *Knis@ ip,'8;;-ip

Composite Error R Current Error Hhase ang!e errorR

Siemens makes S

SIE7E5S


41/73

SIE7E5S


42/73


43/73

Iso!ator

H$6VIFE ELEC$ICAL IS6LAI65 VISI"LE IS6LAI65 ACILIT 6$ EA$4I53 S7ALL C$$E5 I5E$$HI65 CA$$T S46$ CI$CI C$$E5 "

56 6$ "$EAKI53 SC C$$E5


44/73

HA$S 6 FISC655EC6$S

C$$E5 CA$$TI53 A$7S

SHH6$ I5SLA6$S

"ASE $A7E

6HE$AI53 7EC4A5IS7


45/73

THES 6 FISC655EC6$S

46$IU65AL@ CE5$E "$EAK 6$F6"LE "$EAK

VE$ICAL VE$ICAL SWIC4& K5EETHE 6$ HA563$AH4 THE

andem type


46/73

FEHE5FS 65

@5CI65AL $EXI$E7E5

@SWIC4I53 SC4E7E

@EA$4I53 $EXI$E7E5

@C67HAC5ESS *space a1ai!ab!e,

@EC6567T


47/73


48/73


49/73

EA$4 SWIC4


50/73


51/73

Host Insu!ators

A #ost insulator consists of one #ost insulator unit or an

assembly of such units and is intended to give rigid su##ort to

a live #art which is to be insulated from earth or from another

live #art4

@8CTO8!

"us Supports 7echanica! Load Sharing Support Insu!ators #or Iso!ators Insu!ators #or C& CV& C"& IV etc. Support Insu!ators #or Wa1e raps


52/73

Circuit "reaker

Circuit "reakers *C"s, are the switching andcurrent interrupting de1ices.

he C"s are necessary at e1ery switching

point in the substation.A Circuit breaker diers #rom a disconnector

switch main!y in three aspects(

@ au!t current interruption.

@ Arc e'tinction

@ Speed o# operation


53/73

:asically a circuit 1rea*er9C:; comprises ofa set of )+ed a$d mova1le co$tacts"

Co$tacts ca$ 1e operated 1y mea$s of a$operati$g mec&a$ism"

Separatio$ of curre$t carryi$g co$tactsproduces t&e arc t&e arc is e+ti$guis&ed 1ysuita1le media suc& as dielectric oilairsfgas a$d vacuum"

Arc is e+ti$guis&ed 1y le$gt&e$i$g cooli$gsplitti$g or rotatio$"

I$ some 1rea*ers arc is dra%$ i$ t&edirectio$ of splitters 1y mag$etic )eld"


54/73

Rated Voltage

he rated 1o!tage o# the circuit breaker is thehighest system 1o!tage in which the circuit breakeris to be used. his is phase to phase 1o!tage #or

three phase circuit e'pressed in kVrms. Rated Curre$t

he rated norma! current o# a circuit breaker is ther.m.s. 1a!ue o# the current which the circuit

breaker can carry continuous!y without e'ceedingthe !imits o# temperature rise in 1arious parts. he!imits are speci8@8.


55/73

Rated s&ort Circuit :rea*i$g Curre$t 8 he rated short circuit breaking current o# a

circuit breaker is the highest rms 1a!ue o# shortcircuit current which the circuit breaker iscapab!e o# breaking at a stated reco1ery

1o!tage *most!y equa! to the rated 1o!tage, anda stated re#erence restriking 1o!tage underprescribed conditions o# use and beha1ior.

Symmetrica! breaking current is the rms 1a!ueo# a.c. component o# the short circuit currentat the instant o# contact separation. he

asymmetrica! breaking current is the rms 1a!ueo# the tota! current Y comprising a.c. and d.c.components o# the current& at the instant o#contact separation


56/73

5a*i$g Capacity he making capacity is de


57/73

Rated Operati$g seue$ce 9Duty cycle; he $ated 6perating Sequence *Futy Cyc!e, o# the circuit

breaker denotes the sequence o# opening and c!osingoperations which the circuit breaker can per#orm underspeci


58/73

A ransient reco1ery 1o!tage re#ers to the 1o!tageacross the po!e immediate!y a#ter the arc e'tinction.Such 1o!tage has power #requency component p!usan osci!!atory transient component. he osci!!atorytransient component is due to the inductance andcapacitance. he power power #requency

component is due to the system 1o!tage. he heosci!!atory component subsides a#ter a #ew micro@seconds and the power #requency componentcontinues

he #requency o# the transient component is gi1enby (

# 8 -*=ZPLC,# requency o# transient reco1ery 1o!tage & 4[L Equi1a!ent inductance. henryC Equi1a!ent capacitance& arad


59/73

au!t 6ccurs ( As the #au!t occurs the #au!timpedance being !ow& the currents increase andre!ay gets actuated. he re!ay contacts c!ose& thetrip circuit o# the circuit breaker c!oses and trip

coi! is energi[ed. he operating mechanism startsoperating #or opening operation. he circuitbreaker contacts separate.

Arc is drawn between the breaker contacts. he

arc is e'tinguished in the Circuit "reaker bysuitab!e techniques. he current reaches


60/73

CLASSI6ICATION :AS,D ON ARCEU,NCIN> 5,DIU5

AIR :R,AF CIRCUIT :R,AF,R

OIL CIRCUIT :R,AF,R

5INI5U5 OIL CIRCUIT :R,AF,R

AIR :LAST CIRCUIT :R,AF,R SUL?,R ,GA6LOURID,

CIRCUIT :R,AF,R

VACUU5 CIRCUIT :R,AF,R


61/73


62/73

$eco er Vo!tage and bui!d up o#


63/73

$eco1ery Vo!tage and bui!d up o#die!ectric strength o# the medium

5AHOR ?ARTS O6 A CIRCUIT


64/73

5AHOR ?ARTS O6 A CIRCUIT:R,AF,R

INT,RRU?TOR

SU??ORT COLU5N

O?,RATIN> 5,CANIS5

CONTROL 4 5ONITORIN>D,VIC,S

?U5?S 4 CO5?R,SSORS


65/73

INTERRUPTOR

Interrupter houses the


66/73

6HE$AI53 7EC4A5IS7

A. Spring assisted motormechanism

". Hneumatic operating

mechanism C. 4ydrau!ic mechanism

F. Combination o# abo1e

SH$I53 6HE$AI53


67/73

SH$I53 6HE$AI537EC4A5IS7

O#ening s#ring and closing s#ring with limitswitch for automatic charging4Breaer o#eration shall be inde#endent of the

motor used for com#ressing the closing.o#enings#ring4Closing action of circuit breaer shall com#ressthe o#ening s#ring ready for tri##ing4Dhen closing s#rings are discharged after closinga breaer, closing s#rings shall be automaticallycharged for the next o#eration


68/73

?OL, D,SCRI?ANC= his #eature is introduced to detect cases in which one or morepo!es o# a : phase C" remains in open condition where as the otherpo!es are c!osed. his may arise due to ma!@operation or s!uggishoperation o# one or more po!es. It essentia!!y is a timer connectedto a series para!!e! connection o# Au'i!iary switch

ANTI ?U5?IN>

Anti pumping #eature b!ocks the c!osing o# a C" more than once*mu!tip!e c!osing, with a sing!e pro@!onged c!osing impu!se *say&the operator keeps on gi1ing a c!osing impu!se without re!easingthe c!osing hand!e,.

AUTO R,CLOS, Circuit "reaker sha!! be capab!e o# per#orming auto@rec!ose

operation in case o# a transient #au!t. LOCF OUTS AND ALAR5S) S a!arm and L-6) 6perating mechanism a!arm - !ock out) rip circuit super1ision


69/73

) 3uaranteed S !eakage ;.9 per year.) Separate S monitoring #or each po!es #or 8D9kV and

abo1e.) 6perating duty ;@;.:S C6 : min. C6.) S.C. rating D;-9;-:KA *#or D;;kV M ==;KV,

:8.9 kA #or 8D9KV@ Line charging interruption Capabi!ity ;;A

#or D=;kV& 8=9A #or =D9kV*IEC,& 9;A #or8D9kV*IEC,.)

6p. 7echanism Hneumatic-Spring-4ydrau!ic.) Au'. FC*==;V, supp!y 1ariation >; @88; #or trip o# 9 88; #or c!ose.

) = Independent trip circuits& each ha1ing separatepressure switches.


70/73

CSF

C65$6LLE$ IS SEF 6 6HE5 *6$CL6SE,4E C" A IS 76S AV6$A"LEC65FII65

C65$6LLE$ 765I6$S 4ESTSE7HA$A7EE$S*LIKE V6LA3EWAVE6$7,

A5F FECIFE 6HI77 SWIC4I53C65FII65 A5F 4E5CE K56W5 ASH6I565 4E WAVE SWIC4I53


71/73

Circuit "reaker 3A Frg W-o


72/73

Circuit "reaker 3A Frg W-oHI$


73/73

TANF =OU

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Switchyard Equipment