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

.\

I.)

Lat

CE.APTER

SEVEI{

abscissa

of

the intersection

point

of curves

4 and

3

(s

:

sor).

In

this

case

the

i.e.,

by unloa-

increasing

t.he

RAPID

PARA.LLEIING

OF'S}'ISCIIRONOUS

G

ENERATORS

motor can be

pulied

in

step either

by reducing

the anti-torgue,

ding

the motor from

the

side

of

the driven

mechanism or b1'

s1'nchronous

torque

decreases.

Due

to

the

nechanical

load

ses

the

rotor of

the

motor

starts

decelerating

and the

angie

6

The process

continues

until the

short

and

electrical

los-

begins

increasiug.

anti-i.orque.

The

vaiue of

tire

resistor

connecied

for

the

starting

period

in series

ir-ith

the rotor

*-inding

is

3

to

5

times

the

Rrolo,

(R,oro,

is

the

resistance

of

the rot'or

v'inding

n'hen

s'armed

up)

ti-tzJ.

The"operations

used

'to

connect

and

disconnect

the above-n:entioned

re-

sistance can be

performed

b-v

the automatic

starting

devices

both

rvhen

the

rotor

is supplied

fronl

a d.c.

exciter

and

s'hen

a

thvristor.

e-xcitation

circuit

is used.

Inithe

latter

case

the

operations

?re

accompii;hcd

b5

serniconduc,tor

ce

[7-E.

?-1 3]

.

The

motor

remains

in

synchronisn if

the

shaft

load

does not

erceed

the

synchronous

torque

with

angle

6:90

degrees,

i.e.,

when

the motor

is

sup-'

plied

from

the substation

busbars

Ppod.*

circuit is

cleared

and

the

voltage

res-

tored"

If

a

tbree-phase

short

circuit

occ-

urs

at

point

K and

the

residual

volt,

age

across the

substation

busbars

equals

zero,

the

electric

power

drawn

b1'

the

motor

also

becomes

equal to

zero.

As the

mechanical

power

(anLi-

torque)

exceeds'the

elecirical power,

the

motor

decelerates.

If

the'

resis-

fitt- l^o.^. :-. +L- -L--i --.

vt f

e

rrrDDE!\

rrt t

lle suol' t_gllcull

nel_

tlt^:

li

zai#.

e82)

_

Fig'

t-tn;"t*".foin^,"iff#li:lt(:i'

{a)

and

The

value

ot-,9-{,-

*t}-

be

calcu}ated

}1

a

graphical-anaiytical

metiiod

provided

the

condjtio;

S,"'>

S1.

is

satisfied.'

From

Fig'

7-19b

it

ii

ieen"fo.

tlu-l"ri*nce

being

considered,

that

6s1-

corresponding

to

tire

condit,ion

So.

:

S,,,,.

is

tc0

fza

t10

160 r6c

20a

(b)

(7-30)

Usualiy

the

maximum

power

developed_

!y_

"

synchrondtrs

mot'or

(P,,.,)

is

approxim"ttty

two

times

the

motor

load

(P.)

Io

this

case,

normal

opgrlf,o.n

of

,"

w"ohroo-ons

ioi*-i"f."s

place with

anglg

6rr,,

:

30

degrees

(Fig-

7-l

9b)'

\ryith

other relationships

between

P

1oo6

and

Pn and

-F i.lo

vlia:

I J

A6

-

79._

(5loo

d

Plond

(7

-31)

If

for

the

mechanism

T

rn

:

4

s,

then

from

?;n

:

3

s,

tti^

:0.128

s:

and

when

T-r,

J-{=,

(7-32)

tti^

-

tu-

=

0.{05

0.148

s;

when

q

a4

n..

10

60

6C

During

a

short

eircuit

in

the external

power supply.circuit.the

busbar

vol-

t"g.

of

-|ft-r,rppiying

substation

of

the

po*er s]'stem-drops.

As a

result,

the

l6*

it

is

clear

nou'.

that^the

principal

wa1,

to

hold

sSrnchronous

motors

in step

is

the

rapid

ciearing

of shoit

circuits.

Tli*

1'fl'.]:f::^"1:1"^l:tlg

,.:horl

circuit

wi'

be

greater

if

,

during

a shorr

RNPID

PARALLEIING

OF

SYNCERONOUS

GENERA?ORS

:ffi*il*

"^f,

Tl:,=*:::*d:lq_s).nchronous

senerarors

calls for

rapid

resyncb_

'"

"'f

: :,T :^i -ll:,- -

g-!

rs..

af

te5

ie.c

9

r

e,

v

;i,lhe

il;;.

r"lpr

i..

245

lil""i_'j;, i|.. ::l|1*^:.:o^'^..,lle

rerm,inai=

oi

ti,,ir,".irffi,'*J#rr"rfoiTi,jj

T :*

g"

:-: 1.n1h

rnli

za ti

o

n

i s

o

n

iai

ne

a

n

i'ii."

I;il;;iTJ

ilL

rno

ar.

l$":g_l.lhe

unJautred

secrionr

ot ir," po"*

.v-.t.;';;';th;,t#;il:iii#;

**:'::y:,i,'^"yjlii-, ,oJ ::,ir?d,i,v"y1,i1i11.',*i,),-fi

fr)'i"iiiottoe,

the

re'qidual

voltage

is

of the

o.d.,

ot

b.es

u"

lrtr

short,-circ"i,-"rJ|i'ir*1ff'J

Iimit

ooav

run to

1

to

1.5

s, rhe

rime

being

governed;r.;il;;;rilissibre

tirne

a

short-time

interruption

in

power

suppl!.

ln:rn?]:T^,:::]::.,:.ll:,.lnTtia

";iii,

ui.i,*iilri*#"o{

ol{r';i:"f;;;E;

when

after

Fig.

?-20.

Power

characteristics

t-hen

terminal

voitage

of

svnchronous

motor

stator

suddenly

drops

to

65

per

cent

of iated

vaiue

In

this

case

Fig.

7-21.

Changes

in

currents,

r,oltages

arrd

speed

of

sl,ncbroDous

motor

when

,s,

and

rro,

se

.,il.i'ff"::y:i-:,f.':,t:''.lr::"flI;::XT"rl;,,,

;;,"",,,

"

_

speed

The

method

holds

rvhen

t'w'o

conditions

are

satisfied.

First,

the

asvncli-

ronous

conttection

currents

must

not

ca

use

mechanical

d"*"g.

',"',f,.'

;"i",

and,

second.

tlie

characteriJics-

of

the-;j;.J;;-rolgues

and the

anl1-rorque

sliould

allou'tht'motor

t'o

pulf

in

step

u'ithout-beilrg

held

at a i:yposl'nc.hro-

nous

speed.

t;

;'

;;;#;

;;

^

r.;"

"

r,i#'ff

.

"Jt

Jl,'

i

#r'""*i:

:'

?1,

:i:";

:;

"i

Jn

x

di

-*.

lJ

mation

'we

mav

take

the

statJment

!ni.j

it;-*,-".

to

the

mechanical

safet,,,

a

synchronous

iotor

may

lt

.ono*rted

to

"

};ii 'oltage

after

discharging

the

tri^:l/Wl[H

(i-m;

s.

In

addition

'r,o

preventing

the

dearrangement

of

svnchronous

generat,ors.

of a

production

process

dependent

on

the

te

I

rf,'

I,un

the

necessity to

ensure

continuity

2A6

CEAI{TEA

SEVEN

field.

Under

such,conditions,

the

resid.ual

value

of

the

emf

lies

ryithin

0.5

to

0.6

Un.

RAPID

PARALLELING

OF

SYNCI{RONOUS

GENEFATOR.q

z.+ I

Assuming,

for

the

sake

of

safetl',

that

the

resid.ual

permissible

motor

E.^.ry,?:a.4an,

we

find thai

the

equalizing

current

in the

phase

should

not exceed

r"o.-=ry

If

this

current

is

taken

as

the

maximum permissible

for

asynchronous

con-

nection

then,

with

the

reactance

of the

supplying

-s.vstem

er-

and

under the

conditions

when

E^

:

{Jpn.n, the

fol}ov'i"f

'rJt"tlon.hip

_"ho'ia-

be

followed

7-8.

Conctrusions

1-'

In

cases

of

emergenc5',

rapid,paralleling

of-generators

or

parts

of

the

power

s1'stem

may

sometimes

prevent

the

fauit

d"evelipiag

roa

tuiiiitrt"

its

eiimi-

nation.

s

by

precise

synchronization

without

rd

attention

on

the

part

of

the

attending

zation

eases the

operator,s

work,

faciiil

enis

incorrect

actions

by

personnel.

All

emergencl'

conditions.

Therefore.

the

readv for

operation

and

must

nrovide

y

and

voltage

of-the

porver

s-vstem

vary.

regurrements.

eer,

tlrps

ACT-4,

largely

fulfills

theie

emf

of

the

opposition

(7-34)

(i-36)

7.1.2-U

pn.n

t .4U

pn.n

(7-35)

s;here

!.!

:

safety

factor

xi

:

supertransient

reactance

of

the

motor

From (i-35)

it

follows,

as

dictated

b), the

mechanical

safet,r,

of tire

motor.

that

connection

with

the

field

not

discharged

is

permir.rnr.,

-rril;;

.1,;;,

;;;

interruption

in

power

supply

during

no-ci:rrent

inten,ais

in.AF.C

or

automa-

tic

transfer

whenever

r"7

!1rii'4

t,;

t,)0.57xf;

a

detecting

element

has

been

justified

in service.

ose

purpose

rs

con

,3,

C.glorct,ion

of

generators

b5, thr

n,i

jn

service

that

as:'nchroncu_"

c.ontiec-

nous

connection

Is

f"o]-\orv,,l

b).'p:;r"ff

r:i;.HT,:}|,;JH:lirHI:

tt asI'ncirro-

6.

T.fq

points

of

the

power

-"vstei

at

*']rich

asvnchronous

connection

is

permissible

mu'st

be pianned

b.ioruh"na

r,J'

;easures

forersee'

to prevent

#;:ort"tion

of the

prbrecrive

..1u!irrg

,+r;;;

Juring

"ri

r,"tirorro.r=

connec-

",,J;-

11.*t-9:lgyrtni.ns

rhe

possibirit5,

of

asvnchronous

connecrion

of

con-

sumer

.sl'nchronous

motois,

trre

rr*ti"s"il.rr,;j';f

;ir;;*";"il#'ff;'Jrt

;: ff|':

sidered

arid

the

possibilitv'of

iirei,

res'nchrnnizq*inn rrri+1,^.,+ +L^ ---^ -r - ,

.

,

auLonarrc

devlces,

or u,ith

the

use

adapt

the

automatic

starting

drui.r.

i.e.,

when

duration

of short

mentioned

relays

NISM. IO INIS

circuits

in the

of them,

estimated.

It

is

of synchronous

motors

to

good

practice

to

the

asynchronous

supplying

circuit,

the

action

of

the

above-

must

take

place

onJl'

when the

svnch

e oev

etecting

interruptions

to the

normal power

u'hose

value

is determineti

from

eguitious

connectio

The-se

automatic

maint,enance

of

it-s

of

step.

oevlces

nust

promote

load

after

rem'or-al

of

resvnchronlzation

of

the

motor

aiid

the

cau,ses

that

made

it drop

out

errn-1" ^-^ -:*'^*

-uPpi-Y

afc

given

tl

(7-32)

and

(7-33).

^_ ^ ll

s[uatt

'r,ime

deiay

R4.PID

PARAI&ELIN

G

OF'

SYNCIIRONOUS

GENERATORS

rvhen

the

mobr

*j"l^":.1

-hr'3osyncJrrorops

speed

the

c

fjil"fi

jf

:i6d.1*,"i#I'ft"riii.,dai!i"ir"J,".",iHIilJ,#:';"x;*.'!?iiLT

9:::Tr'. 1il

*r"i

scn

resets.

ll". _iyT:lt.

ftowing

in

the

sraror

*orilit:l^f

, *(: .:T

rq.r,"J

-

* ro'

i

i".r"U.

7-9.

Review

euestions

4'

ltame

the

basic

elements

of

the

AQT-a

autosynchronizer

and

explain

their

functjons.

Describe

rhe

operating..princifi*

"i

"

Jiir."J,it"i#"?"i;;;;i;.;;;

"#;T

lead

rela1,.

5.

trtrihat

i-i tire

aiiierer"J

t"t",.ro

;i;;h;;;;;it"*ne"tioo

or

a-

g.oup

oi generators

"'o

u1n-Ji#n;;ttor

r.i.-il,,

;*.i;;-,,]:;;il::"d;",i"rti,,ar

-

--

s

Ervql

system

per*issibllticonditions

is

asynchronous

connection

oigenerators

and

parts

oI

poncr

7'

Hou'

is

the.direct

starling

of

synchronous

motors

accomprished?

6.

What

are

the

toroues

thit m:r.o ! crrnah-^-^rr^ -.^a-- -- rl

g.

llrhat

causes

p.oloneed

;;;n.1'[.;-",;

;1,;;;ii;.":i iil:':,I:.-t^Y'^-11 :votlronism?.

#ff."S:ff::1'-""

i;rlt$:J,lii:'"f;:f."t::1;fi;r;;;;

;;;'i'i;;;';-iJi"'i'rll'aTa";liif,i3-

10'

tjnder

q'hit

c^ondrt;;i

;;;;r1,nClr"o'orrs

connect,ion

oI

a loaded

sl,nchronous

mor.r.

be

performed

if

it,.bas

be-err.

tripped

fronr

-ti-,e

t;"=r'-"i,;iem

1or

a

sbort

periodi

"i",u1L

*:i.;,?",

r:#.??'jli:;

;:;J

d

b"ia".,.,;;;;;;.;.!";;i"^

i"

.ii,"i,,{,",iism

wrier:

short

12'

Describe

the

prinCiples

undeliying

the

-automatic

starting.devjces

of

a

sl,nchronous

f;:nili'j:h

help

irs-res-vnihronizitici,';il;;;r;##,i"[:

Jaulr

rvhicir

cau$cd

tbo

stabijjtt.

"rr""r1j;.'X:il"H#,f

faclors

that

promol,e

resl'nchronizarjon

of

generarors

afrer

their

asy:r-

stator

terminals

of a

sl,nchronous

urotor

l-herr

terruptions

jn

the power

suppll

to

a

sl,nchlo_

riLa

,

The

forcilg

tie

-:-:"'

wJe!

d

ralcol'

br

rp*iegi{%;_fil;

tt:"d

bv

t'he

re6et

time

or

the

rcray

2AZ.R

which

breaks

the

circuir

E.l.r(s

ftle

cffCUft

'n.

"fli'l?'":t.T*";H"if,

f:jl.f;l

A*;;*i :1",f;13,H,,,r?,;oj#X?il."o*.r"g.o:.1,*pl

in

case

of

load

..*C*

CiiltS

Fig.

7-22.

Automatic

startinE

and

resyncfuonization

of

synchronous

motor

lifiJ,l:,ffii:?

f ,'if

:f"",-"',;;i.-q.;:'Ti,;"#;j"?ix""i^'li.

?i

jlf

]:X,'iff

i!'+:i!:::+"i'1il

cl

eenergized.

an0

prepares

lnt 9DE'

rvr

&J

rt'

^+ *-1.:^L

q

!

wllIUtI

rFL

^ -^ -:

r.rru

r-sslsLOf

ft57,

ls

unshorted

a

lne

contactor

ZFK

operates.

f S SnUtrted

bV the c,ont.eef. nf nnn+o^-

voltage

of

tbe

excirii-react;;

;;;1,;-

roieitoa

s/,t

scP

)'_

'uP

{}

K-2

C- t

1

snutt

s-2

*

trF

I

K-4t

vrt

L r

eDrD

lvl

.fl.<

,1

ter

the

terminai"

250

CHAP1rER

SEVEN

Clza,ltter.

Eigtr,t

22.

_A

-synchronous-mgto.r

i-.

provided

rviih

a thl,ristor

ex_cjtation

system

supplierl

lorm

a step-rio*'n

transformer

installeii

on the

busbars

used

for the

suppll:"i;;ir;;]io.rrionou-i

rnotor.

Provisions

are

tnade

to

force

the exci[ation

u,hen

u;il"g;'A;;p."lv'f:

p...uniol

the rated

value.

\\'ill

the

excitatjon

forcingimprove

the

stabilitl'of

the

paralleled

motor

during

a three-

phase

slrort

circujt

accompanied

bl' a v.rltase

droi

acrosi'tlu:.uppr",*j"i,iJ"r.

to zero?

TBREE-PHASE

AUTOMATIC

RECLOSURE

8-1.

General

"

*

*11?,,1i:::*H::

i :Thffi

:?,

"il

Tn x'::, :*"..^T: .

qp+R

c.)

ie

v

i

ces,

s

u

b-

ejemenrs

of

the

power

s'srcm

io

o,"j;;;;;;:;ff^':::::_T'_:"iill

cjose

tripped

their

suppl-v*

ciicuit.

--

vi-ei

LU

iit-i'ui=e

Liie

oonsumer

suppil''

or

complete

L.'*.-r,ggJgIvc'DaILerncAnoP.|Izrno.1l.^+*^_-_...

tht

AriC;._li"i"'#iYi"j.ti*:tf'::y_r_h_.

translnission

rine,

";-d

rhr;peration

of

.

.Sgl"ire

experience

has

also

lnstalled

on

busbars,

since

the

proved.

the

high

efficiency

short

circuits

oecurrins

o;

of the

ARC

devices

El'

virtue

of

the

above'

the

use

of

ARC

devices

for

reenergizing

-the

lines,

bu-*bars

and

transJotttt.

ulr;;,ro-pgLorri-rrrlt.u.tion

circrlars

also

stipur-

ate

immediate

reclosure

of

the

breat

*tr

oi

tirrll""r

erements

by personner

eit'er

252

CHAPTEN

EIGHT

TENEE.PEASE

AT'TOMATIC

RHLOSURE

q(n

rerDoteiy

b1'

means

of

distance

controi devices

or

IocaIIy

by hand

(the

iatter

-onl-r'-u'here

oii

breakers

are

installed).

X'loreover,

after tiipping

a transrnission

line

furnished

with

poye-r

sources

at

both ends, it

must

be'give"n

a

trial

ciosure

supposedll'

from

one

of

the

ends, if the

ARC

devices

acconnting

for

the

double-

end.s^uppl]'-

are

not available

or

are

temporaril;'

inoperativ..".e.o

ARC

device

u-"ed

for

voltage

trial

reclosure

from

one

end

mnit

be ible to

check for

opposing

line

voltages.

The

variants

in

the

ARC

devices

ma1'

be

discerned

from

the follorving:

Tire

action

on the

three phases (TPARC)

or

one

phase

(OPARC)

of

th"e

breaker.

The t5pe

of

equipment,

to

u'hich

the-rrcItage

i.-" applied.

Theie

are

overhead

or

cairle t,ransmission

iines,

transformers,

busba.. rn'd

electric

motors.

The

t1'pe

of

su'itching

devices

under

the

effect of

the

ARC device.

These

are

air- and

oil-breakers,

contactor-q

or

magnetic starters

and fuses.

--

Thc

-tI'Pe

of

po*=er

suppll'

to

the

equipment

whose

breakers are

under the

effect

of the

ARC

clevic.e-

Tliese

a!'e

nn\r-ipr

cr-'stpnr

clpmpntq

"-r-'nnli+d

frnn n*o

or t*'n

pndc

innlrraorl i- r l^^-

",;J,;':-;-::::.^"'^"::i'ii^':,t^nii:I-

rruu

u'ri

a

\Jr

rlJlrrlrlrt

d

Drttgrtr

LIts

LlIlI|.

,rltisirot

(reclosure)

ARC detices.

Eram-

d three

reciosures.

rd

electrical.

RC

desices

(I{SARC)

ensurins

no-po\r-er

rcd

devices

u.ith

time

controf

to

issure

greater

no-polver

inten'als.

ARC

devices

with

synchronism

seizing,

or

at

one

end.

Iines

4-14

and

5--IJ

one

should

also

consider

above-mentioned

ARC

aro.i"".,-of

""

enC

installation

of

OPARC

devices

or

ARC

devices

for

line voltag.

Li;f

..

When

choosing

ARC

deJi"r,

io,

the

possible

use,

ln

additio;-;;

;i"

Tlie

method

of

volfage

controi

across

the

ioacl

detjce.s

responding

to

lo)tage

or no-voltage.

reenergized, as AFC

Tlre

method

for

monitoring

t-lie

s5'rrclironism

cluring

automatic

reclosing

operations.

as

thos-e

u-iiich

respond

to s1'nchronism (ARCSS),

as1'nchronous

ARC

(AARC).

combined

t'itlr

self-s.i'nchronizat,ion

of the

capacitor.<,

tlrose

uiiiclt

contiol

svnchronism.

et,c.

s ano sTncllronous

(AARC).

combined

rr'itlr

self-s,i'nchroniiat,ion

of the

generators

ind sr

Assurne

that

a part

of

the power

s,vstem

shou.n

in

Fig.

8-t neecl

to

be

equipped

n'ith

AIIC

derices.

device

for

a

sectionalized

load

area.

with

preiiminary

d.isconnection

of

station

geDerators

from

the

power.=ryrtgr

toguthr.

o,ith

sonre

loads

of ttris

with

a

suceessful

perform"frr

#th-e-ARc

e;r;;,

on

rines

s_IJ

and.4_r4

lfe

now.er

system

'riar,

itl.-ia-visaUte

to frrr,,ich +r.^ a.__i+^L , r

Tran*"mi-.sion

line.s

I-2-S

are

single feeders

the

pou'er

supplS'

to

tire loads

of subistations

Z

\,-\

--LELLT.

.1-\

J.llle

O-.f

t5

I]oImallv

oDen.

4-5,

crsnsideration

should

be

eiven

to

'with

one-end

suppi-v.

To

recover

and

3, use

rnay

be made

either

of

mplementlng

evlces on lrne

the

variants

of

as_vnchronous

connection

by

the given

transnission

line and the

L's

DeuLronarlzeo

load

area

in

step

with

capa.ble

of

.synchronism

seizure

irr'orAe,

conlrguratiOn

of tlre r..ir"r.rritc Tn - -.,*l

Fig.

8-1.

A

section

of

porver

s5,stem

the

action

-the

porver

si;rr;;;-;th

ff

"tct#|l?fl

to

automatically

reestablish-ii.-no.*rt

local

area.

from

operatton

of

the

sYn-

of

the

AFC

device

in

rs

recovered

to

a value

tirre-e-phase

Aili

devices

or dei,jces

for

phase

l^++^- l^--:^^^ l

br

phase

aut,omatic

reclosure

(the

'.-

'lransmission

line

4-5

connects

two

parts

of

the pou'er

system

incorporating

generation

sources.

Tirere

are

no

other parallel

links

between

these

parts

of

the

of

power

syst€m

parts (AARd)

Iinked

cbronism

seizins

ARC

device

takes

pi*"*-"ii"i"

the

sectionalized'area

and

.it

;;h;

frequenc-v

in

close

to

the

power

system

freguenc5,.

this

area

TEREE-PEASE

ATTTOMATIC

RECLOSURE

255

Consider the-operation

of

the

ARC

device

on

line

7.8.

Substation

8

ma5,

fs

piaced

under

volt-age

irom the

side

of

substation

7 atLer the

synchronous

capa-

cjtor_

(or

t'he

s1'nchronous

motors

of

the

loads)

is deenergized.

After

recoverJ,'of

the

busbar

voltage

of

.substation

8,

the

excitation

sdould

be

automaticaiiy

reapplied

and

the

-synchronous

capacitor

(the

sl,nchronous

motors)

v,ill

restorl

tiie s1'nchronous

operation.

.

Lgop

circuit

1l-9-1A

has

one

point

of suppl-t,,.'frofr

substation

/i.

\4;hen

installing-ARc

devices

in this t5'pe

of

circuit

no

problem-s

arise as to

the

pos-

.

sibilitv

of

asvnchronous

connectibns.

S1'stem

section

4-7-II

has three points

of supp}5',

one from substation

7,

one frorn

substation

11

and

one

from substation-4.

-Under

certairr

conditions,

reclo:-ure

of one

of

the

Iines

of

this

section

mal'

be asl,nchroDous.

\\ihether

such

a

reclosure

is

permissible

and

useful

should

be aseertained.

u'hen selecting

the

ARC

circuit.

Lines

5--l

are

parallel.

The

use

of

another

line

aliows

tire

paraileled

sections

of

tiie

po$rer

q'stem

to

be easih'

controlled

bv

means

of

the

current

in

the

other

operating

iine.

$;hen

seiecting'an

ARC

circuit for lines

5-1. this factor

should

be'taken

into

consideration.

In

practice.

r'atious

ARC

devices

ma1.

be

applied.

The choice

of the

liest

\ariant

is nade

in

tire

engineering

design,

preference

should

be

given

to devices

which

mostll--assure

trouble-free

operation.

simplicitf

in

desi"gn

and

service.

Operation

of the ARC

de'ic.es

must

be

coordinated o'ith

the perTormance

of tlie

piotective

reiaf ing

devices

inst,aliecl

"r:.;1-r;;;uipn,e,rt.

i"

p*rii*olar,

if a sub-

st'ation-

i.s

provided

with

differential protection

means for

th-e

busbars,

consid"er-

at"ion

should

be

given

to

the problem

of

using

the

busbars

of ARC

devices

s,ith

tiieir

preliminarl'

testing

u'ith voltage

from

iny

of

the

transmission

lires rvitir

the suhsequent

automatic

recover-v

of

the

circuit configuration

if

the

busbars

are

in

sound

u,orking

order.

_TnS

operatLng

time

of

ARC

deutces

(for")

is the time

from the i:rstant

the

ARC

device

is

started

to the

time

when

the-reclosure

pulse

is

given.

This

time

should

be sufficient

for

the

breaker

to

be

read-v

for

reclosure

afier

the

short

cir-

cuit is

cleared

u'ith

suhsequent

isolation

of

the

short

circuit if

the

reclosure

faiis.

The

operating

time

of

an

ARC

detice should

not

fs

confused u.ith

the

ARC

time

u.hich

includes

the

operating time

of

tl:e

ARC de.r'ice

and tire time

taken

bI'

tlre

breaker from the

ihstant

lt

receives

tlie

control

signai

to

close to the

toucli

of

the

current-carrying

contacts.

The

automatic

reclosire

time

is

naturally

Iess u'hen

use is made

of

high-speed

breakers.

The

no-power

tnterual

(d.iad-iirne)

is

the

time

from

the

instant the

breaker

arc

exl.inguishes

n'hen

tripping

the

circuit

under

control to

the inst,ant

this

when the'

ARC

devices

were

praced

into

service

it. was

feared

ihat,

after

tripping

the

iine

at-t-he

suootu

gnd,

the

arc

in

the

faulted

pi"ace

*;;i;;.:;;.t"fi;A

9:t

to

the.

energ-v

stored

by

ihe

revolving

iilJ;;l"ur_

ua)

as1'nchronous

and

s5'nchronous

motors

at the

receiving

end

of

the

line.

,

Experien-ce

has

shoun

that,

the

effect

of

the

as],n_

chronous

load

ma:'

p?

neglected

from

the

pliJof

"i.*.

of persisting

agc_ u'itii

c;ferating

time

of

ARC

devrces

ranging

from

0.3 to

0.1s

and

with

tne

otalnati

t";;

Fig.

s-2.

r'ottage

(-1)

and

breakers.

--'r"

fre-quenc5

qz;

r,Ersrii'tinne

e.and

fresuencs,

i""r'ii;f,11?'=l;;?ii,x;

being

disconn-

(ext'eiim-ent"i'air"l'-"

station

busbar.s

n_g

circuits,

.and_capacitor

banks (load

I,,rn,:

60

A;

e,

:2

l.lvar;

and

t].e

bout

0.6 s

the

busbar

voltage

decreased

,

conDection

to

an

unextinguisbed

arc

:---*----

!J vu'

'rrL,,r,.,u

syrsrronous

capacitor."^i*it"il-rJi"iif#"iT.T;

inertia

may

happencircuit

is

restored

after

operation of

the

ARC devi

for otirer voltages,

the

deionization

At the

above-mentioned

uo-power

tirne

may

be determined

by extrapolation.

tine

ratings,

effective

actions

of

the

ARC

devices,

it

ecrdlng

on

be

e

number

should

remembered

one

breakers.

are

two-shot

automatic

reclosures

and

even

more

automatic

reclosures.

be

performed

by

the

ARC

automatic

reclosure

is

the

compli.

of

reclosures

to

that

a

one-shot

ness

to

reclose

the

'

Ivlore

complicated

cated

are

three-shot

a

--!a-rk

in addition

to

this,

as is

shown in service,

the efficiency of

ARC cvcle abruptiv

fal'Is

rn'ith

each

repeated

reciosure-

Thus,

according

to

the USSR

statistics

the ARC operations

to 75

per

cent

effective

in the first

cycle,

10 to

15

per

cent

in

onir'

1.5 to

3

per cent

in

the third.

The

USSR Strt.

Standard

specifies

the

operating

conditions

of

breakers

for

thera

to

suitabl-r:

operate

u'ith an

ARC

device

designed

to

serve

a certain

number

of

subseguent

reclosures.

Symhols

are

used

to

denote

the

breaker

tripping

and ciosing

operations.

The

Ie.tter

O

indicates

an

opening

(tripping)

operation

and the

letter

C, a

closing

operation.

For

instancq

if a

breaker

is

open

and

then

in

the interval

tint",or

it is ciosed

b-r

an

ARC device

and

again opens,

i.e., operation

of

tireARC

device

is

ineffective,

the

process

i*" described

as follows:

O-trn-r"rot-C}.Tire

s1'mbolic

-^+ i+ia-+i^n fi -+ -f O-+.

-C

tnonnc fhet, t,he hrp.akp-r \f,rAs triongd.

uuLrlrvqeLwu v-eintglDl

vv ei'llelDz

tlien

irr

iime

i,n,-,,1-tde

ARC d'Jvice-reclosed

it,

next,

it opened

again

and

v:os

p,"-psatedl_v

closed

in

time

tin,"r,e.

b5'the

ARC

device

and as

the

TEREE-PEASE

AUTOMATIC

RECLOSURE

each

subsequent

functions

are

more

likei-v

as

the

on

iines

are

60

the second,

and

if 1le'

" "

pl"

i

tl*i"

#T

: I

r::

i

;i',

T*ti:: .t

l;^i

T : J1 _o

R

c

.

d

ev

i

ces

wi

th

d

is-

oevrc-e

can

misoperate.

are

liable

ro

punctu".

,oa-in;;'"#;"A.Ii[

l!'".*-.t"*#*,,:l#1,'",:jf

:,'"[tTs',".:l:::'*:

j*llr,canbemadeby

the,power

station

personnel

i+

a

;i

:

il

;1

ffi

:" ifi

t'1"#,

i":3'"o"t1 l **ll tl i

;

i*

;;

devices

"r.

olt"i";i

ffi;;;T-';""ufacrwer

as

complete

units.

!

rv

' ^rrv

qqvrueb

are

oDtarned

from

the

raanufactwer

as

31i lli

J::ffi

:.T;'tS,ff;r",:i

Htr"'l:* ij.":,l ::.:qr

.r

a

ra

ised

weight

or

:Lil

"j

a

co&prer."J-dr;;;ffi

;"+*

ue

stored

energ!'

of

a

raised

weight

or

Such

device*"

were

used

in

3 to ,Jr]t^",9_iTTr._"-ttgpgfc

mryh"i""r

reclosures.

L;1*:in=:;:n::#"i:x#h[lr,ffjf +:]dii=T?tr"TtiJi"i";']:-i:

LHfxffrl

_lh"i

;:

ffi:,"J,"#.,'"11,.T

i:",iJ::i ryJ

:lxH

I

*ix

*_"",Hj

j,"m

mechanicar

ARc

devrces

*

tiilTii,i=.

;;il.fl';.

t;ffi,*#":;"lt"il,r,l,ru

rlx:

CEAPTER

EIGET

Ilata

from

a

Five-year

O-ne_ratiea

of

ARC

Devices

on

tr ,t

t oole

6-l

Overhead

rr:mained"closed

(an

effectirie

two-shot

automatic

reclosure

took

place)'

The

o,peration of

a

breaker

with

a

three-shot

automatic

reclosure

is

l'ritten

down

in

ARC

device

should

be

such

tirat

t.he

oiI

breakers

have enougir

time to restore

their

tripping abilitl'and

the air

breakers

can restore

their

pressure

in

the

com-

pressed-air

mains.

'

The first

pulse

to

reclose

a

tripped

breaker

is

given

[.

th9 AqC

device

in

0.3

to 2 s. tiie

time for

the second ieclosure

is

{0 to

15

s.

The

time

for

the

third

T-rpe

of

ARC

devices

OPeration

parame.rers

Operation

voltages,

1y

z-In

I

2o-3s

I

1ro-iEa

I

22o-sro

I

noo-uoo

Three.pha-

se

single-

snoi,

Three-pha-

se

multi-

shot

Number

of

I t,*\

\

/{

,,

Ef

fecrive

o

oi'o

Periodicitv.

r

effective'

Aq ,?r

c}.65

r\ Ft

v.

t4

5Ao

i?,71i,

I

2.626

I

J65

67.0

1.02

2.08

'12.)

59.5

1.32

1.94

Ql E

og.

b

set-years

peration,

0.25

0.34

0.63

7E.1

0.87

3.10

75.0

c

.77

2 t9,

80.5

0.43

1.75

79

1A

",

a

!.L

/o.J

().82

82

i- o

tl.4

0.34

1.17

w,

80.

7

t t.v

Pha-sc-bv-

phase

-ac-

hng

All

t1'pes

Periodicitlr,

!€?rl

eI

Iective

ineffective

Number

of

set-years

(/r

)

Ef-fective

operation,

%

Periodicity,

year:

eltective

ineflective

Periodicityr

Ve?rl

eltective

31,ts

/u.:)

1 .19

0.43

1.L6

,4

.)a.

,9

.J

0.72

1.28

5.6

Q nro

!sVJL

The singlE:-)rof

peif

the

use of i

siiding

contact

of

a

time relal'.

The

other

of

a capacitor

for

the

purpose.

Each

of

these

variants

tationsl In

the ARC

devices

v'hich include

a

siiding

type

uses

the

discharge

has

advantases

and limi-

ineffectjve

--_

*

I(

denotes

the

number

of

.70

contact

time

relaY,

mal-

i7-2076

the

ARC

devices

(Eets)

times

the

number

of

years

in

use.

2.13

C}IAPTER

EIGIIT

TENEE-PE.ASE

AUTOM]A.TIC

RECLOSURE

C devices

of various

types

are given

in

259

::t,:":Til"'Tf:t:rlTl'"*:,:=-TL.:persists

afrer

deenergizing

the

]ine

or.

if

l;:;:'"t'"'.1:L;i,'J:;Hf"Jn:y#:"_xT"1"1ii!ii'5,i,-T"lli,]x,,"li,r

but

aiso

cable

connection

l"-biii !;;h_;r;1;A#i.::;

when

the

en

rran

ce

co

nn

ect

i

o

ns

"';

jJ#;:

ffi-l,

?,1.1i

?fi

u# :iT

t"":

:fr

iff

h.::

Table

8-Z

Service

Operation

of

ARC

Deviees

Instailed

on Differenf

Eguipment

over

Five

years

t

lf,:trrk

Type

of

ARC

Operation

parameters

comtinea

I

rrnes

I

otirer

eclu

lp-

rsetlt

7;631

64.4

8.25

zJ.d

J/

;

I

,t

r

oree*phase

i

single-

snoI

15.288

56.2

1.3

r

.69

zJc

68.3

)a

.l,rl

2.8

15,513

5i.0

1 14

r.

I

,,,,u,

IlFL.gr

of

set-years

(K)

Effective

operat"lon,'

yo

Perio.dicitl',

vear:

eilective

ineffective

Number

of

set-r,ears

(X)

Fffeciive

operation,'

Zo

rerrodrcit\'.

vear:

effective

inefiective

I't".bgr

of

set-years

(ff)

.ullecuve

operation,

fd

Periodicity,

yearl

elleclrve

ineffecti

ve

I 42

:. ru

o..fd

471

43 .0

{,t .e

8.9

23,314

45.0

4,18

o.4z

{; etl)

60.0

!,J.tJ

o

45.3

15,

829

60.0

8-2.

Single

Lines

with

Supply

from

One

End

J'rl'ealtel's

oI

cable-iines

have

a

smalrer

effectlve

;;;"ti";!L"r'trge,

however

their

use_

fulness

is

evident

(see

Tafl;-s_2]

For

overhead

and

cable power

transmission

lines

supplying

loads

from

one

end,

the

use

of

ARC

devices

is

computso.y.

The

reasons

for

the

use

of

ARC'ar"i.tr

on

bverhead

transmission

lines

are

:lJ,t^"::_lit:l_______________llained.above,

i!*

ARC

a""t"rlnstatled

on

rhe

breakers

of

.Biffective

operation

of

lines

is

accounted

for

bv

the

ARC

devices

installed

on the

breakers

of

cabre

the

fact

that

the

breakers

trip

not

only

recau.*-oi

"

Fig'

8-3'

Three-phase

single-shot

ARC

de'ice

started

b1, p'otective

relal,ing

17i

260

CSAPIB'

EIGTT

t

The

contact

ATR-2

closes the

auxiliary

relay

lAR which

in its turn

makes

the

coii

circuit

of time

ryigv

ffi.

Siiding

contact

S

promoGtiU.

pre-assigned

operatiag

time

of the

ARC

device,

then

end

contact

2

by

its

closing

relJases

the

circuit.

i";i^-";;:.^;i.:"-:i::::--".':-".'^";::'^,,:":.':'oJ

u,'rl

rr'ab

bwu

.,'ur'.D'

ru€ serres

uorr

:g

vlv---su

r..Y

u!.\i

rur.1y

uuuLacLs ror

rfie

LIme

enoug.o. Ior Ing

DrgaKgr

1o

closg

aoo

its

ilocking

contacts

open.

The

time

deiar-

of

the

end

contact TR-Z

is

such that,

it

overlaps

the

time

taken

b1

the

breaker

to

disconnect

from the

protective

relaf

ing

circuit

r*'hen

connect,ed

to

a

persist,ing

short

circuit. If

the

time

delav

of end

contact 2

is

time

margin is from

0.7

to {

s.

The

circuit

intended

for

speeding

up the

action

of

the protection

is

shown

b-v

the

dashed

iine.

If

the

breaker is connected locally

from the

switchboard

or

from

the

load-

dispatching

department

b.n* a

remote control system

then, after tripping,

the

breaker

should not

be

reclosed

as

the

cause of

the tripping

is

very

likely

to

persist.

An example is a manual

closure after

repair operations because

of

un-

connected

earth

f aults

or

bad

repairs.

This

requirement

is

met by closing

the

breaker

manualil'b5'feeding a eontrol

puise

to the

relav

TR

ol

the

ARC

device.

With the aid of

the

knife

switch

KS the

ARC

device

can be

removed

from'

tbe

operation

with the

direct

changing over of

the

c].osing

circuits

to

the

closing

coil

of the

breaker.

Provision

may

be

made

to

remove

the

ARC device

from

the

operation

automaticaliv when

the

breaker is

closed by

the

controi

ke5r s1

3

remote-control

device.

This, ho$'ever,

makes

the

circuit more complicated

and

therefore

cannot

be

recommended-

Tltree-phase

one-shot

ARC

deui.ce started wlten

the

breaker

are

in

dtllerent

positions.

When the

breaker

is

tripped

by

the

and,

the control

keu

protective

rela

S.YS uncorresponorng

posltrons

Detweetr

lne

DreaKer ano tne

control l{ey

clostng

4-5

(Fig.

8-4a

and

b)

occur. Because of this, the

operation

of

the

relay

ne-shot

three-phase

ARC

device,,

type

pflB_sg,

started

and

control

ke1,.

are

in

different

positions

circuit

lAR

is

u'hen

breaker

oontactor

stack

flemen{s

ol ARC

ffi:"ro*ttt'

'"to,

Closing

ol

Lreaher

StartinS

of ARC

derice

Circuit

ol relau

lor

protcc!rcn

occeterbtaan

after

IRC

prohzbition

(-)

L2P

followed

b-v closure of

the time

relay TR.The contacL

TR-Z

of

this

(a)

d

everoped

dia€ram

:

tfJ,'ir33g

"bff

"1'o'%$'*'#'Iff

'J#;i"f

3'*f

u

ot

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

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