Barzam A.B. Automation in Electrical Power Systems (Системная автоматика)

THREE-PETA.SE

AU?OMATIC

RECLOSURE

283

If

the pickup

time

of the

tirne

reray

is

tpichup

the

beat

freguencv

/^

_

6i,

_

6|r"n,r,

(1

*

ft')

,':33T;il:-6q6-

(8-r4)

When

fr,.

:

0.8,

Opicnup

:

40o,

and

tpiehllp

:

2 s

l,:#(t+o.s):s.}:0.1

Hz

When

k,

:0.85,

dprcnup

:

b5o,

and

fr;.1up

:

2

s

l":0.74

Hz

Used

in the

device

shos,n

in

Fig.

g-{Z

as

the

relay

cliecking

the

is a

rela-v

responding

to

the

vector"dift"r.o"e

l.t*;;;

the

'olt?ees.

angle

6pichup

Such

a-relav

Fig'

8-16.

operation

of

AR'c

device

with

synchronism

seizing

(a)

changes

of

angle

between

erol vectors

in

asynchronous.operation:

(b)

operatilg

range

of time

relay

of

ARC

device

(the

ranle

area

is

iifoiteo

Dy

angle

otr)

To

l/.E

pmtection

or

tin*

(6)

Fig.

8-18.

connectiou

of.synchronism

check

reia1,

to

coupling

capacitor on

the

line

and

to

voltage

transforrnei*

on

UuJl.*"

(a)

connection

diagra-;

(b)

pector

diagram

IU

r,*n-l:

l4g!

-ltrt_Uzl

$45)

A

tt

utt

utu

u2

(')

(b)

Fig.

8-17.

Synchronism

cbeck

relay

(o)

diagram

explaintng

operating

principle;

(b)

relat

connection

pay

b-e

a

voltage

relay

whose

coils

are

opposing

each

other.

Applied to

one

coil

is

the

busbar

voltage,

while

the

other.reliit"irir

rt tn*li"L

"iit"g*

taken

from

a voltage-

transformer

or

from

a

device

f;t

;;;;itor

voltag"

l"k;-off

which

i.s

connected

to

the

line

(Fie.

&ig).

Ihe

relav

oicls

up

if

-tle

tttoltiog

flux

in the

relay

core

is

greater

than

the

flux

co"rerioodi$

&

1q-

.pirt"p

voltage.

diagram

=

I

-l-

I

IC,

I

icz

I

lu2

(t)

CE,I^PTER

EIGET

TEREE.PEASE

AUTOMATIC

RECLOSURE

co*espondingto

the

pickup

voltage

upichup

is the

angie

6prchup.

If

1

u,

;

:

I

U,

[,

then

If

the

co'ntacts

r-scR-l

open

tir

the

ope{ation

of

the

contact

rrR4,i.e.,

if

the

trequen-

cies

differ

bv

more

tuan

o'z

fri''tl'"

""i1

"i

rrh!-;i*;"Jii'o""o-es

deenergized

and

the

cir-

cuit

of

the

ARou,

is opened

li'ti,.-"o"otactlVilfl"iii?tr,"

contacrs

Ise}-zhave

closed.

LIJ

:2U

sin

$

L

Being. given

the.

required

setting

of

angle

dpichup

naay

be determined

as

foliows

rr 07:

dPichurr

u

Pichvp:

LU

Sln

-3-

(8-16)

the

'ioltage

across

the

relay

(8-17)

!17hen

the

relav.rang€

is

limited,

the-

angie

between

the

vojtage

vectors

(6pi"n,,p).,af

which

the

reJay picks

up,

can

be riidened

if

one coil

of

the

relav is

connecied

to

the uglr,rg:.aoo

"oa

tfi.

oi-rrcr,

t,

in. ,:rltil;

:-u;;

"i,

ilj.'ir]

st.a.nt

the

additjr:ne'!

s-hift ho+i,o^-

+I-^ =.-^'!r

Tf ^.o nf +1.o -^i:^^::i:'::"^'-::"'' .""Y ,""t.t'ogt

Yeclors

wru

amount

to

bU degrees'

5i

uii-

t'i L-tiu

iuia:\'coiis

is

eonllect.eci

to

the

voitage

[,ro

and

the

other,

t-o

t]re

at

a

pickup

angle

adjustable

within

the

other

re1al'has

a setting

range

from

tting

range

is

:t70

degrees.

f tbe

ARCSS

devices,

reclosures

u,ere

performed

improve

the

operation

effjciencr

oi

tle

AnC

nergo

designed

a scheme

whjcl: insures

parallel

'anging

from

0 to

1.9

Hz with

a

marimuir

ansle

I

and

its

closing

contacts

make

wlen

the pbase

s.

As

this

bappens,

tbe

time

reiav

JI.R'pick.

anergized.

AftCr

tbe

contact

oI

IA'TR

iras

one.

rugh

the

self-bolding

circuit,

as it

is conneiiea

Fig.

g-I9.

ARC

device

'nith

synchronism

seizing

P.R

-

conract

of

pressure

re)a1.

(*h.#.,r.%lir?if;.,

",rl*"*"rl

I

BC

_blocking

con_

lljlr^|"^qlgngjittgrence^js

sTall

(tess

rhan

0.T

Hz),

t]re

time

rel

-CBus

Retay

to

close

6rea*cr

0ne-shot

oDerstton

and

resei

relau

iscn-?-op"n.-fl;;i&i;.rsi;:r:ffJ{'""",1".",31!?::TJff

f#T'.'#g#:r#i,"""fjl;j:

the

outprit

relay

,{-Ro",

-t"""tibi.-*a

croses

tbe

breaher.

CE.A.PTER

EIGET

TERES-PEAsE

AI]TOIdATIC

NECLOSURE

device

must

iaclude

a voltage

relav

to

,no

voltage

exists

across

the"busbais,

a

hronism

of

the

line

and

busbar

voltages.

]ine

no-voltage

condition.

al til

;&;

ge

across

the

line

and

busbars,

and

the

.e

is

no

voltage

aeross

the

iine'o,

"*r*.

the

no-voltage

condition

and

when_the

fhe

s;'nchronism

seizing

relays

t"""tioo

The

slrrchronism

seizing-ARC-device

waits

for

the

time

u,hen

parts

of the

power

system

may

be paralleied.

This

is why

.u"i

ARC

devices

m"y

l.

regarded

as

plain

automatic

sln'hronization

devices

faciil"ting

the

work

of

the

operators

i::?T!1i:hings.-vnchroi-ism

when,

on the

ora.r-oilne

disparcher,

the

frequencies

ot the

sectionalized

parts

of

the

power

svstem

are

egualized

nrior to srrhspnrrpnr

txr11"_'11s,

q'

when

rhe

conditions

carxiog

rh;

AfrA;;;"';i;;

";LT;ii;n";i;

Aiu

del'rces

have

operated

in

the

part

of

t[e

sect,ior"fJ-a

p"";.r-.i"i*"*rr.i.

real

power

is lacking.

8-4.

Tie

Lines

and

parallel

Linl:s

:Iosures

in

a

ring-t-vpe

system,

the

fol_

k)

Resulti

!

JLTIfor

relo

Contrcl

stona! ta

close

b7eake,.

i

td.des

=

4.4

s

Breaher

closed

luitehtno

aver

cottacts

ol

rcldv

25CP

ContTot

stgno.l

lc

tc{^ricr

I

=U.+

g

close

6Feahe.

-'-':

'

:-''-',

Starting

lfR

Dreah?r

closed

Ttme

ol

slidtno

contact /TR-l

4f

--

E;'ea.ttr

c[osee'

tc|

dc"

-u.a

s

Ttne

bl

sltdtno

EOaLOCI lll!'4

Control sional ol

clo,te

6re6*cr

(c)

Fig..8-20.

-Operating

diagram

of ARC

device

circuit (Fig.

S-19)

depending on

the

difference

between

freguencies

of

the

voitages'being

synchrLnized-

(tl

connection

at.treguency

diftetencesup.to

0.7

Hz;

(b)

same at

frequenc] ditference

from

o.i tn

1.3

rlz;

(c)

same

at lreguencl'-difference

frbm

1.3 to 1.9

iizl i.,;-"

-

daic;

closure time

from

the

instanr

f$"f#fr?"j,jr€li,rji"c;L1"ol?

J,o"

rnstant"'tb'e""conracrs

of

Therefore,

in

man-v

cases a

no-voltage

check

rela_v

(with

a

vieq, to promot,ing

the line

tests)

and

a

synchronism

sefzing

relay

lwit!

tlie

object of

Jlosing f";

paraliel

operation)

are

instalted.

Tire

automaiic

reclosure

time is

set so ihut

the

brealiers

at,

both ends

cannot

be simultaneously

closed

*-hen

the line

is

tripped

at

both

ends.

When

the

line

tripping

from

both

ends

may

render

tbe busbars

of the sub-

station

connected

to

one of

the

ends

deenergized

(for

example,

due to disconnec-

tion

of the generating

plant),

the

ARCSS

device

cannot

function.

In

this

case.

Automatic

reclosures

stations

serving

transmist

tce

when

unatteDded

sub-

breakers.

If

AHC

de'ices

d with

remote_controi

line

much

time-*ifir

proronge

,tJ:f"llr:rations

will

tahe

(b)

An

ARC

operati6n

rakers

at

both

ends

of

the

line

are

reclosed

aiter

the

at

the

il*;;iault

mav

th

ends,

otheru'ise

tbe

arc

"

(.r;;iil;ffi;,;

li?'iti,-ilinh

subsrarions

of the

ring

circuiLs

with

oi

ena

sufply

""r6tions

whe

turn

out

to

be

under

one-

con'itinna ooah arra^+i,,^ ^,-4^_ -a.

nected

for

repair.

In

such

(b)

ff

r*t#r.;il!1,

eff

ecr

i

ve

a uroma

ri

c recro

sure

pr"

uroii"il;i"il"

;"

ffi#*i;;:ff

The.ring-lings_employ

ARC

devices

of

the

same

one

end.

The

ARC

deviCes

are

instali"a

"i

tir.-ii;

type

as the

lines

supplied

at

ends

and

make

the

breaker

Svitchinq

orer

L'oDtacts

{ rctav lSCP

S*-ttching

orcr

contacf!

ol

.l

relay /SCP

.

I

--\

Jt,"

45"

ffR

ttt.

,t'

in

parallel

with

the

contacts

of the relav

controlline

the volta

chronism

rcelnsp oftor i+o +Fi-*:--

s-uvr

^uD

urrPPIuB.

trEAPTER

EIGETT

TEREE-PEJ,SE

AUTOMATIC

RECLOSURE

Sometimes

to simplify

the

protective

relaying

s-vstem,_a

ring circuit

(with

one

power-suppll'

poirit) i! disconnected

to form two

parts. In such

instances

the

po*er suppiy io-

tirese

parts with a line

short circuit

is accomplished

as if the

iubstationi

are fed

fronr-one

end. The

loads

of one

part

of

the circuit

are

switched

over

to

the

other

part

manually

or automatically

only

in the case

of ineffective

"

n"dit;$""iJ,lit*Ti?*:'i-f

b

de

v ices

wthour s

ynchronism

check

a re insra

rre

d

if, when one liak is

trippetl

the otber

link is

permitted to asyncbronously

close

afier'its

opening. If asyochronous

reclosures

cannot

be

tolerated

the

lines of

a

ff*fficomplished

by

a

current

relay

connected

to

the

current

of

the

other

The

oper"ti19,^Tl:t-rp

om

Fig.

*21.

Automatic

reclosures

-o

he

current

relay

connected

rnd

vice

versa.

I_f

the

ARC

B-4

the

presence

of

curreni

;ime

relay

?,R

inciuded

in

contacts

of

a

current

relay

tiippe{

ar

the

or1,."_,

,"u,'?i:

l',1,1T

::'rruTri'#ti:l,t:'.fffiu";oj?.:*rltffi#

the

vaiue

of

the

line

capa.rty-ri.r.ot.

8-5.

TPARC

Devices

on

Air

eirerrit

Br.*akers

:ircuit

breaker

from

an

ARC

de*ice

is- permitted

only

pressure

in

the

breaker

reservoirs,

rliore

the

first

su_fficienr

ro.accompiish

the-con;i.;;;

of

the

first

iosure

from

rhe

ARC

J..,rir.,

,"d

;;;;iJ,

trippiug

if

rs

rated

at_35

to

b00

k\/

the

minimqm

piessures.

at,

arariees

rcriabie

shoit

circuit

cieari'g-

are

taburat,ed

@

I

z

.

ring

circuit

are

equipped

with ARC

syn-

chronism

seizing

devices.

When

three and more

paraiiel

links

are

availabie

between

the

power

stations

of. a

rtng

networkwithseueral

power-supply

- -:--r^ -:---l+ l:^^^-*^^+l^- ^S ^ l1

UUULI'T'

bIII.'[|.IIUAIIT'U

|.IJ TIIDUUITl-rT'U|JIU.TI

(JI

AIT

ihe iinks

is considered

unlikel--v. That

is

whf it is not

necessar-v

to use

more

ela-

borate ARC

devices. The

lines are fur-

nished

with ARC

devices

with.out s5'p-

chronism

check

as it,

is in a ring circuit

supplied from

one

point.

Taking

into

account

that fauits m-a:,r

occur repeatedh'

during"repairs,

ARC

devices

providing

synchronism

checks

are

sometimes used.

Such

ARC

devices

ensure

tripped

lines

reclosures onlv

when the bvpass

links

Fig.

8-21.

ARC

device

circuit

rvith

check-

ing for synchronism

remain

in operation,

i.e., when

the.

power-supply sources operate

svnchrono-

usl-v.

The

ARC

devices

incorporate

elements

which check

the

voltage

s-vn-

chronism

on

bot.h

sides

of

the

breaker being

reclosed. ARC

operations are

prohibited

if t,hese

voltages

lose synchronism; this ma]'

irappen

when all

b5pass

links are tripped.

The

ARC

s-vnchronism seizing devices

and

s]'nchronism

checking

ARC

devices differ

from

each other in that

the former

automatically

perlorm

reclo-

sures

n'hen tire s_vnchronism is sustained

or,

in

the

case

of

disturbances

to the

synchronous

operation,

"siezes"

the

most favourable

instant

t,o

give

a

control

pulse

to

reclose

the breaker at a

fairiy

iarge slip,

whiie the latter accomplishes

automatic

reclosures

after a

preassigned

time

lapse if

the

synchronism is

not

dist,urbed

during this

time,

or conditions arise

under

which

the

disturbance

slip decreases

to

a

permitted

vaiue.

Tlre

ARC

devices

for

parallel,

Lhrcs

have

the same

underiving

principles

as

the lines

of a

ring

system.

Use is made

of

the above-described

ARC devices,

in

particular

the

ARC

devices'with

svnchronism seizing and AARC

devices

where

asvnchronous

reclosures

are

permissible.

The specific

configuration

of the

circuit

allows

parts

of

the

power

system to be cireckcd for

synchronism

after one of

t

-

As

tripping

a-

breaker

decreases,

th9

"g*ptes_sed

air

pressure

by

3

kgf/cm2,

t'he

pressure

availabie

after

the

iirst

tlq;g

ilf*e

the

reclosure

from

an

ARC

de'ice

shouid

be'

to

"rlo":iot'pottili.

reilosire

due,to

a persisting

short

circuit,

Ff

l'['ltf,'+fuHx:T,Hlliiif"**i[;"t:*:.."+.*s:rg.shorrcircuit

n

'rv

ksr/cm'ror

BBH-220/7000

"oa

nfiutsdo'ri."rii#

ffiXT.,:::

kgf/cm2

for

orher

tvpes.

These

."r.*i;;;;

iJi""i"r,

accouat

the

facr

eomDressed

air

consumption

tor

etos-i{".rh.

ff;ier

is

smag

and

that

Compressed

Air

pressures

at

Breakers

Clear

Short

which

Air

Circuits

Circuit

T-vpe

of

brcaker

than

21

.

that

the

t9--2076

BBH_35

| ,_

BBH-220,/7ooo

I ii

BBHR-5oo

I il'

Breakers

of

other

types

| ;;

Z.D-J

9<e

r)

I

paraliel

lines

wit,hout relay checking

the

voltages

for

synchronism

is

tripped.

90n

CE.APTER E"IOET

the

compressed-air

loss

is repleuished

in

the tripping-reclosing-tripning

cycle

from

compressed-air

mains.

C,ertain

air

hreakers

control

circuits

provide

adjustment

of tbe

compressed-

air

pressure

and the trigger

circuit

of

the

ARC

device by

an

electrical

pressure

gauge

as shown in Fig.

8-22.

The

ARC

;

device

will

operate onlywhenthe

pres-

sure indicated by the

pressure

gauge

PG,

after tripping the

breaker

and

closing

the

contacts

of the

opening

soienoid O.9, exceeds the

pickup

sett-

ing.

In

this

case, the relay

Ll?,

which

holds itself

closed by its

AR-I

contact,

function and completes

the

ARC

device

triggering

circuit by

its

AR-z

contact.

The relay

.AJ?

remains

closed

until

the

self-holding

circuit

is broken

at the

contact

of

the

breaker closins

solenoid

(C-e;.

A likely

pressure

decrelse

in the

opening-closing cycle

does

not

stop

the action

of the

ARC

device.

T- ^-l^- a^ --'l-^ eL^ --^--r:-- -f rL- L-^-r--- ^ t -1^---. --

.

t

tn oroer

ro

make

tEe

operation

or

itre

breaEer

eontrol devree

rnciependent,

oi

pressure

drops

likely

to

occur

during its functioning,

provision

il

made to

Fig.

8-23.

Control

circuits

of air

breaker

CK

-

eontact of

'control

key;

P.R

-

contact ol

output

protiction

relay; O.q

-

contacts

on solenoids

of

opening

coils

1in

phases

B

and C);

iS

-

contacts

on

soilnoids or closins

coiis:-Bd,

Eb,

B.-

blockingcontactsclosedwbenA,Band

Cpbases.of breakerareclosedl

:-{f.R-relay

n'ith

dropout delay

up to

5 s;

2r4..Rspr-

series coll of rolay b}ocking

agairut

multi-ahot

reciosures;

sAR

-

auxiliary

relay; C glq

n

-

capacttor and

resistor to lmprove

arc

exuneurshrng

bypass

the repeater

relay

contacts

which

control the air pressure

by the

blocking

contaets

sJlhe

e,leetr+u+aga-etie

elosi+g+nilepeai+g€eilsJa

addieie:n;+rensur+

.^li^L1^.+-:..i.^^f+L^^:-L.^..r.^-J^r^.3_-..l-_-_7lrL^r.l

rei-ia.oie

-u+pping

oi

-',ne

oir iir=€aii€rs, provisioB

ls

made

fo

"piei{

up"

^rne

irrpprng

pulse

with subseguent

interlocking

after

the

hreaker

has

tiippeilfor

about-5

s-

0l

-

prelbttinarv

opened

02-

open

o

-

opened

C/

-

pretininory

l

ctosed

I

.C2

-

ciose

C

-

closed

0

aot

ctctc

lllzszttll

toAR_t

Irt

+

AR

Fig.

8-22.

Circuit

for control

of

starting

circuits of ARC

device in

air breakers

bv

rneans

of

electrical pressure gauge

9AP.3

To

Lus

of

audi6le

warning

stgnalling

1so-r

I

-t--l

'I

2P6

7o

6us

ol

oudihle

faal.{

stgnollmg

0 mot

(

0&0r

ilac

\

aF i.'

-dlP-?

H

8q-lg

oau

sQc

ttt24rrr

Proteclton

caatac!

tJtEi

tune

Aeldv

Fuscs

ood

*nile

-syitches

tcrcuits

ol

AnC

dcvicc

Closing

circuits

t!'

-5\

ig

rt

Pilot

tanp

OFF

Pttot

lamp

O,U

Tri2Ting

circuits

Protectton

and

accclerqiton

circui{s

Iimilatton

of

trtppzno

pulse

duratidn

"

.No!

-alI

-phases

trtp.oed

indiealioz

Air-pressure

indtcqti

Iow

oir-pressurc

YArntno

fna't.catton

of

ARC

operatzon

tArP-t

fin-z

il

%U,-*'

'1"

EeBa

-5

BCEa

-

5

,9.

CEAPTER

EIGET

The

circuit

emplo5's

a

two-position

a diScrepanc5'

arises

between

the

positir

in

the

case

of its

disconnection

from

th

.F.R

closes

the.circuit

of the

ARC

devic

Ited-by

the

electric

pressure

gauge

IpG.

ql

tl:

pressure

gauge

contactl

op-ens

and

tll ZAR,).

In this

case,

the

ZAR_

Z

and

bingcurrent

from the

closingand

opening

rate

at

pressures

belo.tr.

16

kgf/cm2.

ae'r,

of

iFG

rcakes

anti

the

leiav ZAR

i the

breaker

is recovered

as

u,ell-as

the

pllted

by

the

contacr

ZAR-I

(with

the

IAR-I

is

open

s'it,h

the

result

that

the

:ted

q'hen

the

compressed-air

pres_qure

ts 2AR-2

and ZAR-J

are

holding

coiis

closing

or

opening

operation

if iuring

rre

becomes

]ess

than

16

kgfrcm!,

a laci

rperat.ing

circuit,

the

contact

s 2AR_2

i,

and

2ARB

are

conrrected

in

pal.allel.

on of

the

position

rela5,

CpR

anc

CpR

than

16

kgfrcmz.

8-6.

Conclusions

TEREE-PEASE

AUTOIUATIC

NECLOSURE

I'

ARc

deYices

T,',]:li

jiport,alJ

as the-v

improve_rhe

operation

reriabiliry

ij"f::: :r:T'^T._..1*:i;"

o^:].]:f:9

tu,.o--ni,q.,*dn"c-

"a-i;";fi;;"il;:=:ffiii;i

from

one

end

or trvo

end's

,t.

oo'o1il"""r+ii.'i"

,rr.

ilssR:

?:,Tl:r*19_o^.:::::,1:rg-oo

iines

supplieaat

on*

""alr"

specia'-v

imporranr

:::*t:,:jlii'",1:.*llli::

prevents

outiies.*ith

i;i;;s"d

i'Jr""".ipir"Tfl;T#

p

o

";.'

;u

f

t

;

.1

;'

q

d

i i

; ;

;i i#'j

.'

:

: lX-"'

i

#.l:,

fl

:?'

ffi

A'

uT,:t'#,"

lJ

i

a dvisabie.

T:-$_lLasgclro:ol:

AR'c

device

;i;.*-;;;^

J;;j;*"i"^

"ri

",;r"i:;;;

;ff

mechanical

efforts

in the,generators

"-oa

trr"nrior*r".

caused

r.,'

"lr"lilil;:

f'.,1^T:1.r,

do

no.t,exceed

th-e

rated

"at"".,

;;; ;il;;;fiIr;;;o"i

i""rosures

are

*],t""_Tj l:::lt:u .1"r"#l:':i:l!,:",

t:;n1;3gry

iil.-i',"r""Ttiil

;:hd;:fir:il

must

be

adapted

to

the

operation

of

4'

'1ne

exDediencv

of

ARC

use

in

a sectionalized

area

should

be

corrsidered

l:,:*gt;l:^p.,"-T':

:1,:l:: llll_ffi

; .d;ffi,io,

a

su

p pr

i e

d

from

th

e po wer

Starl

af tPC

device

Aeah-r

rlat'

nn

Brea*er

lrippin"o

Fittng

relay

cLotcrtg

Fig.

8-25.

Control

circuit

of air

hreaker

s'ith

ARC

device waiting

for

pressure

""

-#T;iito'

,.,",'

iliustrated

i-n

fig,-&!4.

This

diagram

shows the

above-mentioned

pickup

of

the

trippihg pulSe,

*hich

may not

be used

for

tbe

BB-200, BB-22A-ana

BB-+OO

breakers having-devices

for the

pneumatic

pickup

of

the

control

pulses.

Figure

8-25 shows

one

more

variant

of

th-e

ARC

circuit

of air

ciicuit

breakers.

A

specific

feature

of this variant

is its

ability

to

perform

automatic

reclosures

with waiting

for-i,te pressure

fo

builtl

)

when

it

has

dropped

during

the

accomplish.uent

of

the

control

pulse

cleiring

a

.short

circuit.

tsR-l.

Bt-E

c,s,

'A*7

?AR,

BR-ser

dC-o

_!

itl

Irl

irl

tii

1-TT

lll

system

through

a singie

transmission

l"ine,

the-#;;;;"r;;il

;Hi

";;r#_*;;

CEIAPTER

EIGET

TENEE-PII.A.SE

AUTOMATIC

RECLOSURE

8-7.

Review

Qrestions

1'

tJPhy

does

the

cause

of the

fau]t

often-disappear

after

ciearing

a

short

circuit?

what

is

meant

bv

an

effective

automatic

"""io"*"i-rfli't'6'"ii"iines

the

effi-ciency

of

ARC

devices?

what

accouDrs

tol

l!:

effe*ive"

operarion

"r

Aric-;;;;;;;;;ff;'""#drrit"r

^. ^,2:^llh-{

j:-!l:.

percentage

of

eiTective

tu":fi;;

r-rto*"ti.

"""r"r*iJ

Fearer

than

rhar

o

I srngle

automatic

reciosures?

fr_"H:-"rn

operatiag

time

of

ARc

devices

o

tio"i'aaas

to

the

reiiable

operation

of these

erplain

this

fact?

r

-o-neend

supply

line

is

under

reDair.

The

line

May^

you

reclose

it

immediat^ely

manually

ment?

yrng

a

poyer

system

area,

be closed

manuallv

recrosed

by

an

ARC

device

and

again

trippei

or

sing]e,

two-shot

and

three-shot

automatic

'er

to .ioads

from

one end!'

]tages

of

the

ARC

devices

started

from

a

oro_

rrted

x'hen

the

brealier

aad

the

"Jrt"ot

f"y-^"e

the

device

sho*n

in Fie.

g-4?

m

siugle

actio!

and

twd_shot

action?

Sketch

ll

circuit

breakers.

,l

=

,10

y,

rhe pick-uu

voirage

ol

2AR

rcIay

acitor

C:20

pF.

re

contac[or,

the

capacitor

C

starts

to

charse.

;ne

moment

its

coil

is activated

b-"_ a voitige

7"

across

tbe

capacitor,

becomes

greitei

tn"-"

he

relay

coil,

the

voltage

across

the

terminals

:'the

law

where

(J

c

:

rt

_

v-

t_

a-

voltage

across

rn"

""p""rt*".

-g'-t/R'c

voltage

to

which

the

'capacitor

u,.as

charged

time.

s

tt^

j:-*J.

More

accur"

r",

rli

fll;?

i:H;r,

(8-18)

fr,

i

resistance

of the

coil

of

relay

ZAR

ce

the

relav 2A F talros .

"..t-J--i

l-^ ii ^-

sincd the

relay

2,4r1

takes"

".rt*in'il*,i

iJ,ii-,""rt. ir ic no^o--6--, r^- +L^ --^ru

;apacitorterminalsto

hp.at ioocr ?

"

-^

"t;tl1p^t^"*e;i1-s

necessarS'

for tbe

voltage

across

i.e.,

it must

be

(e)

The list

of lines

for v'hich

tive

automatic

reclosure

mwt

be

manual

reelosir'lg

is

compulsory

after

ineffec-

established

beforehand.

e

capacitor

is

charged

to

the

law

IJc:IJbotT

-c-tlRC)

(s-rs)

for

actual

t5ryes

of

rela

ys

is

deter-

(&20r

1.1

Mohnr.

where

mined

k":

e

--L^-^ D:^.L- -r.

vc:ubdt'-

w',nrv

'^

' lrrr

cuargrtrg

reslstance.

In

the

exampre

we

assume.ft _

CEAPTER

EIGET

Clt altter

hrin

e

_-_,- 9urily

determined

from (B-19)

and (g_20)

js

rhe

chan

voirage

airosl

ii"

capaciror.

r,lJ"[L',

iil iiru-*';;

;i;;';i,s.tig,"ti.*r_t

tg"irJi#t::#]:t]utl;

liir"lfltl,'j"i;rli,t,

reliablv

function.

eft"'-i[i.

ti'.';;;"ii;'

starrs

ro

discharge

rhrough

the

tcharse:

RC

ln

#frr,"^""

lcharse:1,

100,000.20.

10-6

fn

ir5#hZ

tclwrse:22

ln

2.5

=

20

s

Hence

(B-21)

(B-22)

ONE-PEASE

AUTOMATIC

RECLOSURE

OF POWER

TRANSMISSION

LINES

14'

Estimate

the

different

methods

of establishing

AR

C der.jces

on

single

tie lines

between

tr*'o parts

of

a

power

svstem.

under

"'nif

io"aiiioL-i.;;';";;i;r"d"i;

ii.ifi;

asynchronous

automatic

reclosures?

20.

What

are

the

r:cl,iotrs

of

tl-re

opere[,or-s.

,*-hen

-tbe

transmission

line

is tripped

when

the.tripping

coincides

io-ti*"

*itn

rlil

"h;;Ii"g'"p;.rii""

of the

ARC

devjce

(rhe

ARc

device

s'as

disconnected)?

9-1.

Earth

Fault

and

Tripping

of

One

phase

The

devices-used.,for

deTecting

a

faultv

phase

and

the.protective

relayi.ng

units

operating

together

with

theie

aevicei

il;;.

more

complicated.

298

CEAPTER

NTNE

ONE.PE,A,SE

.I.UTOMA"IC

RECLOSE

RE

299

, .Whcn

oru-ol

the

phases

ol

the

circuit

Iault,

the

voltage

of

the

faulty

phase,

fault

is

zero.

usith

a dcal.+artlwd

r:lr;utrals

is

at

an

earth

say phase

.4 in

Fig.

g-2,

at the point

of

Table

9-I

Phase

d is

at

Earth

Fault

The

current

at

the

ttrip

-

fault

triPPing

time

point

of

short

circuit

l"

7

__Ee_O

_

Eo

t

Aec:

--

'where.

e

:

impedance

equivalent

to

that

oI the

short-circuit

loor

E

a

:

nominal

emf

value

of phase

r4

ABC

5C

Fig'

9-2'

cuments

at

one-phase

e-artlr-fault

point

in

circuit

with

heavy

earth-

fault

current

Using

the

met

as

a vector

sum

of

forward-,

backward-

and

"r.olrrqoro"*

Currente

at

Sbort-Circuit

point

when

/c:o

ic:iu*

t

tcztto

Inn

_ A"u

L./'1

"z\l

In.

LL

?l

t

r:

'.81

The

currents

in

the

undamaged.

phases

are

i"r":0

and

fa""

:

0;

thw

n-i , i I

v-rBlscTig2scr/0",

o:

icrr"+'i"rr"+

i*

These

conditions

and

condition

(g-t)

are

satisfied

iJ

f

^r"":

f

nzu:

f

o""

.

in"r:3i0""

ra

e

s.

\

$

-

j":

o

i":i"r*

*itr*io

i. ,l\. T

oo

lP"'

tr,

'1

/ar=*x

x

(ia+4,;3+

*"2i

c)

r^t

.1

I.a.z:*x

d

x

(j,1

qazita

*oic)

io:**

x

(ja*

rfrt\

ttBttC)

rno

rurro

tr

I:g;^?:1:-lermissible

no-power

lirne

due

ro

tripping

one.

or r.hree

Trhases

with

suDsequent

reclosure

versus

dis[ance

and

uv.pe;]

;f-"Epl;;-;.;il;-r':;il;:p;;;

ARC

device

as

dictarsa

lr'

*;-ru"iiiiii

or

power

rratrsmission

line cver

rvhich

tbe

power

station

suppli"es

power

[o

power

system

and

in

the

For

rents

/Ar:e,

/.er'c

and

forc

by corresponding

sequences

syslem

of

voltages.

-

.

phase

A at

the point

of short

circuit

the

voltage

oa

(s-2)

(s-3)

L

-f

I i

r;

t

Ana-

I

tlto-f I aq-^ + r^--

a&tw

|

-

UJL

cuments (Table

9-1)

(e-1)

The

volta

E?s.

U

n,

and

Ur-o

decrease

and

the

voltage

tionnl f.n the disf.o-ia f"r- TLo *^i-+ ^+ ^L^-r -:-^--:4

_Eservv

rrv.a

e4e

l,urJtu

vI

DIluIl,

|Jll,(irrrL.

Pbaee

currents

at

short-circuit

Symmetrical

componerrts

ol

crlrrents

Sequence

of

phases

f or

ward

':'"=f

!:t"n

0

50

t00 6A

200

250

J00

J50

t00

+50

kn

f/^,

increasss

propor-

CEAPTER.

NINE

At the

substation

trf tbe

voitage

of this

sum

of.the

voltages

of

the

given

sequence

at

drop

of

the

corresponding

lequence

due

to

Takiag

into

accouni

(9-5),

we

determine

the

fauity

phase

voitage

at

the

point

of

the

relay

installation

at

substation

M

i

on

:ilo,"Lr,n

,"

+

i[i"rr*.".

f

.rf;6".eor".

(9-6)

The

voltages

of

backv.'ard

sad

oo-^. oA-:i^:.-..1.-

zero,

a

s

the

r"-r

u."io*i-

io.*

;"J,;#

;:;

1il:::ri::"J:r.$:J:;:l

i[TJT.il;

(9-5)

may

be presented

as

folions:

inr:

Enn.:Unrrra

inrr"zrr

(g-7a)

0:

b

nr""-;

lrr..)z:

(g_?b)

S:

U6r.

f

.Io*;Xzo-

(g_7

c)

where

Elrn:

nominal

emf

of

the

pha-se

/

Err,

Xer,

and

2;;;

:

s]'steno

forward-.

luJt"=rAl

and

zero-sequence

impedan_

ces

reduced

to

the

point

of

short

circuit-

*o.tli,_l|il*il:fi:uit

for

the

short-circuit

calcuiarions

is derermined

through

As

at

a

single-phase

short

circuit

the

short-circuit

point

satisfies

conditions

(9-2)

and

(9-4),

u,e

have

ONE.PEASE

Af'TOldArIC

RECLOSURE

with

arl

open

cireuit

in

oru pha,se,

say phase,a

Fig.

g-4),

the

c'*eut

phase

is

zero

and

the

voltage

between

the

m.

and

n

open-circuit poihts

EZox

<__

f^

:.f

.

atE

ttC

zsc

(')

F

io

q-c

F

n,,ir.r^-+

".

sYq

vqrqu!

-:----:a ! .

:,,:"^:i:

y.,f*r,ll,f

rll-q

!

cyrrenrs

during

one_phase

shorr

vrr

vqr

u

lvr

Lrr

qeae_eaf

t,ned

neutfal

(a)

general

case:

in

this

.-:

ls

U,1.

he

vector

e

voltage

guence

(e-s)

and

the

(b)

for

lin-e

su,nplied

at

one

end

with

eartbed

a1-ifiJ-iilpityrng

ano

receiving

*rteutrals

of

ths

tu'ansforluers

,*f'rilr;*1t:.

*"t.

be

presenr"-d-.."1

o_riginaring

of

direcr_axis

(longirudinal

-e,*,t

yurr,d,H'

asross

the

open

circurt,

gap

q^rd

\

AEo.

:Uo

l.ti"g

superimposed

on

the

symmetric

vortage

sl,stem

of

the

tion.

more

accurate

we

proceed

as

follos,s:

As

the

current

i

A

:0,

then,

in

accordance

with

the

basic

relitionships

of the

syumetrical

component

method,

we

have

i

^:/o,

*

i

nr*/o:

0

(g_{

i)

The

components

of

tbe

forward,

backward

and

zero

seguence

of

the

direct-

axis

voltage

at the

poi.ot

of

open

circuit

are

(s_10)

before-fault

opera-

ino:i0,.1:r,

*

2zz+

Xzo)

-Thus,

the

equivalent

circuit

aust

represent

a

series

pedances

Ezr,

f z,

""a

83.

(rrauJ.a

to

ii;;;;;;t

of

shorr

the

nominal-phase

enf

(FL.

g_3):

The

current

at

the

poin"t

of

sirort

circuit

(e-8)

conrection

of

the

im-

circuit)

which

are

at

; _

Sinn

-aow-frT-*-

Lzlf

LZo=

LzO

of

the

circuit

is

determined

section

under

consideration

(e-e)

as a

sum

of

currents

in

compliance

s'ith

zero

sequencies.

the

impedances

in

Fig.

g-3b.

The

current,

at

any

point

flowing

through

the

iystem

the cnrrent

distributisnli

If the

line

is

supplied

at

one

*rA-tior.rr*pf.,

#.]J

zt'

:

zzN

:

m

and

the

equivalent

circuit,

has

the

rn

compliance

with (g-2)

the

point

"

*r,

!2,

tsnd.

zno

from

one

side

of

the

open

circuit

are

at

similar

potentials-and

F#

#'i"i*r"onnected.

The points

from

the

other

side

of

the

bieak

;;,,;;

r"a{u."

"i*

"q,riporenriar.

the

It[ side),

form

shown

EZrt

EZzt

,%,

-+

-->

ru

rzfi

tz*

.{---

ro"r=rl"r=rr

*

Barzam A.B. Automation in Electrical Power Systems (Системная автоматика)

Подождите немного. Документ загружается.