sensibilty analysis

7/21/2019 sensibilty analysis

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Universidad De La Salle. Serrano1, Mondragon2.Impacto Dispositivos FACTS.

Abstract — In this article the impact of clearing FACTS

(STATCOM and SVC) in a power system IEEE ! nodes" whose

location is determined from steady state analysis (sensiti#ity analysis

and c$r#es V%&) to maintain a condition occ$rs safe operation

related to the system #oltage sta'ility

System analysis of ! nodes was performed on a stage of maim$m

load (*+,+M-) as a tool to s$pport the .E/0A. software $sed to

r$n power flows and the respecti#e steady state analysis of power

system

Keywords 1FACTS" Voltage sta'ility" steady state" maim$m load

I. INTRODUCTION

Te e!pansion and increased demand in e!isting po"er s#stems generate a negative impact on s#stem voltage

sta$ilit#, "ose sta$ilit# is related to te increase or decrease

o% reactive po"er &'(, so #o) m)st ens)re voltage operating

range in all nodes o% te po"er s#stem ens)ring a sa%eoperating condition relative to te limits o% ma!im)m po"er

deliver# s#stem reactive present.

To ens)re voltage sta$ilit# and sa%e operation o% te s#stem,

reactive compensation devices are implemented, s)c as

FACTS compensators "ose operation is $ased on po"er

electronics applications, spanning te voltage sta$ilit#

pro$lem one o% te pro$lemsIt is presented to determine te

optimal location o% reactive compensation devices in te

s#stem, %or "ic di%%erent anal#tical tecni*)es developed in

sta$le condition to determine te location o% compensating

s)c as+ sensitivit# anal#sis &-'( and Modal anal#sis c)rves

-'. Tis article %oc)ses on te sensitivit# anal#sis &-'( and

' c)rves on a standard I 1/ s#stem 0odes %or te

proposed ma!im)m load in te $ase case o% 2.M3 $eing

and standard o% operation voltage o% 4 156 o% rated voltage.

II. APPROACH OF PROBLEM

For te location o% te devices compensation FACTS it is

important to identi%# te critical nodes o% te s#stem %or "ic

a sensitivit# anal#sis &'( is developed, and li7e"ise it isnecessar# to determine te limits o% ma!im)m operating

compensators reagents "ere it develops ' c)rve anal#sis

on te node "ere te compensation s#stem is located, ten

te development o% te t"o anal#8es presented a$ove9

:

Sensitivity analysis V-Q

It is $ased on te st)d# o% voltage variations "it respect to

te in;ection o% reactive po"er o% te load nodes, "ic elps

to identi%# te most sensitive s#stem. *)ation &1( so"s o"to represent tese variations in voltage over cange o% reactive

po"er.

<= >? -1 @ <' &1(

<9 Cange in te increase in voltage magnit)de node.

<'9 Cange in te increase o% reactive po"er in;ection.

>? 9 ?ed)ced >aco$ian matri!.

Te elements o% te inverse >aco$ian matri! red)ced &>?-1(

represents te sensitivities '. Te components o% te

diagonal represent o"n sensi$ilities vi B 'i indicating tesensitivit# o% te node "it respect to imsel% and te o%%-

diagonal elements represent m)t)al sensitivities 7 B 'i

"ic means te sensitivit# o% te node "it te s#stem.

Te sensitivities o% te voltage controlled nodes are 8ero. For a

proper interpretation o% te sensitivit# anal#sis it is clear tat9

ositive Sensitivit#9 Indicates tat te s#stem is sta$le, a smallsensitivit# val)e indicates tat te s#stem is more sta$le,

leading to as te sta$ilit# decreases sensitivit# increases.

0egative Sensitivit#9 Indicates tat te s#stem is )nsta$le, $eca)se $e%ore te in;ection increases reactive po"er voltage

levels drop in te s#stem. It is said tat te s#stem is not

controlla$le $eca)se te control devices are designed to react

"it an increased $e per%ormed a%ter an increase in '.

C!ves V-Q

Te st)d# o% tese c)rves is $ased on voltage collapseinterpret as an indication tat tere is an inade*)ate $alance o%

reactive po"er in one or more nodes o% a s#stem. Te c)rve is

o$tained $# increasing te reagent cons)mption in eac o% te

$ars o% te s#stem or at least tose considered "ea7er )ntil tecollapse. ' c)rves o$tained ave a U, in "ic te lo"est

point represents te point o% collapse and reactive po"er

margin in tat $)s.

Te a$sol)te minim)m tat range in ever# $ar s#stem te

margin to voltage collapse. An e%%icient metod %or planning

te net"or7 is considered. In oter pala$as it said te po"er

Serrano, Leonel 1 , Mondragón, Jaime2 .

Universidad de La Salle

Bogot !.", "olombia

sleonel#$%&nisalle.ed&.co1 ,m'aime#(%&nisalle.ed&.co2

IMACT SESTMS F CM0SATI0

FACTS I0 T?A0SMISSI0 SESTMS

1




margin indicates te amo)nt o% reactive po"er compensation

re*)ired to restore an operating point or o$tain a desired

voltage val)e. It is also de%ined as te minim)m val)e tat canincrease te reactive po"er cons)mption o% te load or te

decrease o% reactive po"er generation %or "ic tere is no

operating point.

oltage collapse $egins in te "ea7est $ar s#stem and ten

e!tends to oter "ea7 $ars. Te "ea7est $ar is te mostimportant in te anal#sis o% voltage collapse. Te "ea7est $ar

is one tat e!i$it one o% te %ollo"ing conditions9

G It as te igest critical point.

G It as te lo"est margin o% reactive po"er.

G Has te $iggest %ail)re o% reactive po"er.

G It as te igest percentage cange in voltage.

It can $e seen in Fig)re 1, te s#stem is sta$le "it ligter

load 1. For tis load, tere is a reserve o% reactive po"er

&'reserve( can $e )sed to maintain sta$ilit# even "en teload increases. Te s#stem is marginall# sta$le "it load 2.Te s#stem is not sta$le "it te largest load , an amo)nt o%

reactive po"er &'missing( so)ld $e in;ected into te $ar to

ca)se an intersection "it te ! a!is and prevent voltage

collapse. Tere%ore, meas)ring te amo)nt o% reactive po"er reserve &'reserve( ma# provide an indication o% te margin

$et"een sta$ilit# and insta$ilit#.

Fi" #. C!ves V-Q $%! &i$$e!ent l%a&s.

III. METHODOLO'(

To st)d# compared te SC and STATCM, te 1/ nodes

S standard I, "ic is ta7en as $ase case "ito)t

capacitors s#ncrono)s nodes , and is cosen s#stem. And

r)n po"er %lo" in order to ave a point o% comparison &$ase

case( %or losses and voltage sta$ilit# o% te s#stem to locate

FACTS s#stems in te s#stem.

nce te $ase case, "e proceed to per%orm ' sensitivit#

anal#sis to identi%# te most critical s#stem "ere te location

o% FACTS compensation s#stems re*)ired nodes.

Since te parameteri8ation o% tese FACTS s#stems depends

on te amo)nt o% ma!im)m and minim)m reactive device and

sa%e operating range o% tension "itin te s#stem set "itin 4

156 o% te voltage nominal.se an anal#sis o% ' c)rves in

0LA0 to set limits reagent in;ection device.

Finall#, as a res)lt o% te sensitivit# anal#sis te most critical

s#stems nodes is determined $# coosing te t"o most critical

to te percentage o% sensitivit#, and %or eac case o%

per%orming te anal#sis o% te c)rves ' to determine te

limits o% reactive compensation %or FACTS devices ta7ing into

acco)nt te operational limits esta$lised voltage.

I. RESULTS

Cosen %or te case st)d# o% s#stem losses, tensions on eac

node and i% presented overloaded nodes are o$served.

Fi" ). Dia"!a* Test syste* IEEE #+ Bs.

In Fig)re 2. Te $ase case diagram, consisting o% 1/ nodes,

t"o generators, t"o tree-pase trans%ormers J B 1. 7, 1

tridevanado trans%ormer loads and 15 is ill)strated

Base Case, Flo" AC "ito)t compensation.

)ABL* 1

+owers + and S*+ wit-o&t comensation.

2




Symbol &antity S/" S)A)"0M

/ /er M- *2"33 *2"33 & /er MVar ,!"44 ,!"44

/ 5en M- *64"*3 *64"*3

& 5en MVar ,*4"334 ,*4"334

n la ta$la 1. Se m)estra los res)ltados al correr el %l);o AC en

0LA0, donde se m)estra la relaciKn de # ' de perdida en

el sistema, as como la # ' de generaciKn.

Fi" . V%lta"e levels . /ase 0ase.

As co)ld o$serve in Fig)re . Te $)ses %rom to 1/ present

overload in te $ase case, ie te# are $elo" te criteria %or sa%e

operation o% te s#stem voltage, "ere$# a reactive

compensation "itin te s#stem is re*)ired.

Sensitivity analysis V-Q

Te %ollo"ing sensitivit# anal#sis is presented ', "it "ic

te most critical nodes o% te s#stem is determined.

Fi" +. O1n sensi/ilities.

As so"n in Fig)re 2, te most critical nodes are 1/ and 12,

$eca)se its sare o% sensitivit#, "ic means tat tese nodes

are closer to insta$ilit# and are cosen to intervene "it

FACTS s#stems.

Fi" 2. Mtal sensitivity t% t3e n%&e #+.

Fig)re so"s te sensitivit# ratio o% te node 1/ "it oternodes in te s#stem, to $e more speci%ic reagent a contri$)tion

%rom node 1/ as an in%l)ence on s#stem nodes.

Fi" 4. Mtal sensitivity t% t3e n%&e #).

Fig)re so"s te relative sensitivit# o% te node 12 "it

te oter nodes in te s#stem to $e more speci%ic reagent a

contri$)tion %rom te node 12 as an in%l)ence on te nodes o% te s#stem.

From te a$ove, FACTS devices are located at nodes 1/ and

12 to ma7e teir anal#sis. For eac o% tese nodes ' c)rves

are o$tained, in order to determine te reactive po"er

necessar# to maintain sta$ilit# and node parameters determine

$ot te SC and STATCM.

C%*ensa0i5n N%&% #+

Fi" 6. C!ve V-Q n%&e #+.




-' c)rves are )se%)l %or determining te $o)ndaries o%

reagents %or FACTS devices regarding te sa%e operating

limits o% te voltage and te parameters re*)ired $# 0LA0

to node 1/.

Ten %lo" carging compensation >an node 1/ is per%ormed

and te %ollo"ing res)lts are o$tained9

)ABL* 2

+owers S*+ + and comensation node 1.


/ /er M- **"77* *2"33 & /er MVar 7!"*34 ,!"44

/ 5en M- *62"+7* *64"*3

& 5en MVar 3!"!*, ,*4"334&C aporte MVar !*"672 !*"672

In Ta$le 2 te res)lts "en r)nning te %lo" AC in 0LA0,

"erein te ratio o% and ' so"n in te s#stem loss, te

and ' generation displa#s. And te s)ppl# o% reagents

necessar# %or te setting o% ma!im)m s#stem load %rom te

node 1/.

Fi" 7. C%*ensate& v%lta"e levels %n /s #+ $%! SVC an&

STATCOM.

In Fig . It can $e seen tat te o%%set %rom te node 1/ $# te

SC and STATCM, generates te same e%%ect on te s#stem

voltage pro%iles, since te anal#sis is done at stead# state.

C%*ensa0i5n N%&% #)

Fi" 8. C!ve V-Q n%&e #).

-' c)rves are )se%)l %or determining te $o)ndaries o%

reagents %or FACTS devices regarding te sa%e operating

limits o% te voltage and te parameters re*)ired $# 0LA0

to te node 12.

)ABL* # +owers S*+ + and comensation node 12.


/ /er M- *!"7+ *2"33 & /er MVar 74"36+ ,!"44

/ 5en M- *6+"++ *64"*3

& 5en MVar 46"6 ,*4"334&C aporte MVar *,"4!+ !*"672

In Ta$le te res)lts "en r)nning te %lo" AC in0LA0 ,

"erein te ratio o% and ' so"n in te s#stem loss, te

and ' generation displa#s. And te s)ppl# o% reagents

necessar# %or te setting o% ma!im)m s#stem load %rom te

node12.

Fi" #9. C%*ensate& v%lta"e levels %n /s #) $%! SVC an&

STATCOM.

In Fig)re 15. It can $e seen tat te o%%set %rom te node 12 $#

te SC and STATCM, generates te same e%%ect on te

s#stem voltage pro%iles, since te anal#sis is done at stead#

state.

/




. CONCLUSIONS

In;ecting reagents tro)g te STATCM and SC is te

same in eac case st)died, $eca)se te# m)st $ring te node to

te rated voltage, so te di%%erence $et"een te compensation

"it eac o% tese devices is teir operation and its mode o%

operation.

From sensitivit# anal#sis ' #o) can determine te optimal placement o% devices o% compensation, since as so"n in

Ta$le 2, te active po"er loss "as red)ced $# appro!imatel#

6 o% te $ase case, in addition to sta$ilit# tension is

maintained in te operating limits o% 4 156.

N# implementing compensation at te most critical s#stem

node &node 1/( sa%e operation in voltage compared to te

lo"er percentage representing sensitivit# &node 12( is

o$tained, tis can $e seen in Fig and 15.

To ma7e compensation at critical nodes sta$ilit# is o$served

tro)go)t te s#stem, 7eeping all nodes in sa%e levels o%

voltage, eiter te SC or STATCM.

Te reagent in;ection &'c( o% te device decreases as te

percentage o% sensitivit# o% eac node ', $)t tis is re%lected

in te increased loss o% active po"er s#stem.

Te limits o% reactive po"er &'( ' c)rves o$tained

according to FACTS devices, are val)es tat can $e acieved

in real s#stems, "it re%erence O2P "ere tere is a

compensation capa$ilit# 4 255MA?.

VI. REFERENCES

O1P Song" 8" 9 :ohns" A (666) Flei'le AC

transmission systems (FACTS) /ower and Energy Series

O2P ISA crea n$e#a filial dedicada al transporte de

energ;a en Colom'ia (,7!) Ingesocios edici<n 2+" ,!",2

OP =r$gnoni" M (,776) Sistemas Flei'les >e

Transmisi<n En CA >?cimo Tercer Enc$entro @egional

I'eroamericano >e Cigr?

O/P ing" 0 %" >$" %" 9 Bho$" - % (,77)

Comparison of application of SVC and STATCOM to large

capacity transmission path of power system >ianli itong

=aoh$ 8$ ongDhi/ower System /rotection and Control"

*4(,!)" 33%443

OP 0iGie" >" 8ang" 0" 9 8iH$n" M (,77) Comparison

of high capacity SVC and STATCOM in real power grid

/aper presented at the ,77 International Conference on

Intelligent Comp$tation Technology and A$tomation"

ICICTA ,77" 66*%663

OP Idris" @ M" 9 0oh" S (,72) Modelling and

sim$lation of STATCOM 9 SVC /aper presented at the

/roceeding % ,7* IEEE St$dent Conference on @esearch

and >e#elopment" SCO@e> ,7*" 3%,

OQP Tan" 8 0 (666) Analysis of line compensation 'y

sh$nt%connected FACTS controllersJ A comparison 'etween

SVC and STATCOM IEEE /ower Engineering @e#iew"

6(4)" 23%24

OP Tran" T" Bha" " 9 0e" . (,7!) /erformance

comparison 'etween STATCOM and SVC to enhance power

system sta'ility

OJP M @odr;g$e" KL'icaci<n de FACTS para meGorarla esta'ilidad de tensi<n" ,7,

O15P : 5 = Valerino" K0a esta'ilidad de la tensi<n de los

sistemas el?ctricos de potencia $tiliDando el programaN/SAF" Ingenier;a Energ?tic" #ol *" nP ," ,7,

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sensibilty analysis