rơle khoang cach micom p44x

Rle khoang cach MicomP44X

Bi:

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Rle khoang cach Micom P44X

Gii thiu chung v rle khong cch s micom P44X

Cc rle khong cch MICOM l loi sn phm ca h thng bo v v iu khin caALSTOM T&D. y l mt trong nhng loi rle k thut s c ng dng cc cngngh hin i nht hin nay. Chng c th cung cp cc kh nng bo v ton din chocc ng c, my pht, cc xut tuyn Z trn khng, mng in cp, Z c b dc...Nh vy, cc rle khong cch s MICOM P441, P442 v P444 hon ton c th png c cc yu cu bo v cho tt c cc TBA truyn ti v phn phi bt k cpin p no trong h thng in.

Cc rle khong s MICOM c tch hp hon ho c phn cng v phn mm, chophp x l mm do, chnh xc cc tnh hung s c gn, xa, s c chng cho. MICOMc mt th vin vi y cc s logic ng dng cng nh cc s logic kh trnh,kt hp vi kh nng o lng, thu thp - x l nhanh cc tnh hung xy ra trong hthng v a ra cc phng thc x l hp l cho tng loi s c. c bit l nh ccthut ton d tm chun on tin tin m rle khong cch s MICOM c th phn onc cc tnh hung s c trc khi n thc s xy ra v hin th cc cnh bo khngnhng v cc ch s o lng m c cc dng sng v th vct ca chng thng quacc cng truyn thng s hin i.

Ngoi phn mm ci t cho rle, MICOM cn c phn mm m phng vi giao dinging thc t vi cc ca s Window phn lp a nng, ng thi c th lp trnh v ktni trc tip vi cc rle thu thp - truy xut cc d liu thng qua h thng modem.Do c th dng phn mm ny phc v cho cng tc o to, hun luyn ci t rlekhong cch.

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Hnh dng bn ngoi ca rle MICOM P441 (Hnh 5.6)

Ngoi chc nng chnh l bo v khong cch, MICOM P441, P442 v P444 cn cungcp chc nng bo v khc nh chc nng: qu dng (50/51), qu dng chng chm t(50/51N), qu in p (59), in p gim (27), TL (79), t chi ct (51BF), chng daong cng sut (78), chng ng in vo im s c (50/27), kim tra ng b (25)...

Cu hnh chung ca rle khong cch s MICOM:

Hnh dng bn ngoi ca mt rle MICOM P441 nh hnh 5.6.

Trong :

(1): mn hnh tinh th lng (LCD) c th hin th 16 k t di hai hng. (2): bn n led c nh. (3): tm n LED hin th vng kh trnh. (4): h thng cc phm chc nng. (5): phm chc nng c, xo cc k t v hin th thi gian. (6): v bc v k hiu sn phm. (7): tm che chn bo v cc u kt ni cng truyn thng. (8): phn u kp ch.

Ngoi cu hnh chung nh trn, cc rle khong cch s MICOM h P44X cn c ccc im ring nh sau:

P441: c 8 u vo logic cung cp cho mn hnh hin th v cc chc nngkhc, 16 u ra truyn tn hiu ct my ct, hin th thi gian, truyn thngxa v cc chc nng khc.

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P442: c 16 u vo logic v 21 u ra s, ng h ng b thi gian thc, ccu ni truyn thng vi cp quang.

P444: c 24 u vo logic s v 32 u ra, ng h ng b thi gian thc, ccu ni truyn thng vi cp quang.

Thi gian tc ng nhanh nht ca rle khong cch s MICOM c th t c khong18 msec.

Rle khong cch MICOM c hai loi cng truyn thng l: cng truyn thng ni b(local communication port) v cng truyn thng t xa (remote communication port).

Cng truyn thng ni b: gm cc mch giao tip tun t c thit k sdng kt ni trc tip vi my tnh thu thp cc d liu hay ti cc chngtrnh, cc s logic, cc thng s ci t khi s dng phn mm m phng S1hoc kt ni gia cc rle vi nhau.

Cng truyn thng t xa c s dng kt ni vi cc thit b truyn tin traoi cc thng tin gia trung tm iu khin vi rle, hoc truyn tn hiu ctlin ng gia hai rle hai u Z... Nh cc cng truyn thng t xa mngi ta c th xy dng cc TBA vn hnh hon ton t ng khng cnngi trc, t c th nng cao tnh t ng ho, kh nng ng b, tincy cng nh cht lng in nng trong h thng in.

Cc li ch ca vic s dng rle khong cch s MICOM:

Rle khong cch s MICOM P441, P442 v P444 c th loi tr mi s c mt cchnhanh chng l nh vo vic ng dng kt hp gia tc x l ca phn cng vinhng gii thut ti u ca phn mm, lm cho bo v tc ng c tnh chn lc v tin cy rt cao. Khng nhng th, rle khong cch s MICOM cn c tch hp rtnhiu cc mun c nhiu chc nng khc nhau nhng rt gn nh, iu ny lm choMICOM tr thnh mt bo v a nng m khng phi bo v no cng c c nh:

Tiu chun ho cc cc rle cho tt c cc ng dng. n gin ho cc ph tng vi cc u vo ca bin dng (TI) v bin in p

(TU). Khng cn thit phi c thm cc bo v b sung nh: bo v qu dng (50/51),

qu dng chm t (50/51N), bo v in p (59/27), TL (79), kim tra ngb (25), bo v chng dao ng cng sut (78), chng ng in vo im sc (50/27), s c my ct (50BF), cc thit b t ng ghi li trng thi s c,cc thit b o lng...

Chun on li nhanh chng vi cc thng tin li, nht k s kin v cc thngk li.

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Cung cp kh nng bo v ti u v kh nng t kim tra bn thn phn cng,phn mm nh b gim st h thng. N c th kim tra tnh trng ca TU, TI,my ct...

Tng cng tin cy cho bo v nh s dng hai k thut o khc nhau. Thi gian x l v thao tc rt nhanh, c th t n 10 msec cho chc nng

qu dng v 18 msec cho chc nng khong cch. Mt h thng th vin vi y cc s logic ng dng cng nh cc s

logic kh trnh. Cc cng vo/ra s tc cao, c bit l cc cng ni trc tip vi h thng

cp quang thng qua cc u ghp ni m khng cn b m. Cc chng trnh m phng a dng, d x dng chy trn mi trng Window

cho php hun luyn cc thao tc ci t trn m hnh cng nh cng c th ktni giao tip trao i thng tin vi rle.

Cc ng dng ca rle khong cch s Micom h P44x

Chc nng bo v khong cch:

y l chc nng bo v chnh ca rle khong cch s MICOM. N gm mt h thngd tm s c, mt h thng o khong cch v mt h thng xc nh hng cng sut(dng in) s c.

Chc nng chnh ca bo v khong cch gm hai phn: bo v khong cch cho s cpha (21P) v bo v khong cch cho s c chm t (21G).

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Bo v khong cch cho s c pha:

S bo v Z ca rle khong cch s MICOM (Hnh 5.7)

Rle khong cch s MICOM P441, P442 v P444 c 5 vng bo v cho s c pha vc ch ra trong c tuyn tng tr t gic c trng hnh 5.8. N c th bo v c ttc cc s c pha xy ra trong vng tc ng ca t gic c trng v c nh hngnh sau:

Vng 1, 2 ,3 l vng tc ng theo hng thun, c dng nh mt bo vkhong cch ba cp thng thng, ch rng vng 1 c th m rng n vng1X (vng 1 m rng Zone 1X) khi cn thit.

Vng P (Zone P) l vng kh trnh. C th chn theo vng hng thun hochng ngc.

Vng 4 l vng hng ngc.

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T gic c trng cho s c pha (Hnh 5.8)

T gic c trng cho s c chm t (Hnh 5.9)

Bo v khong cch cho s c chm t:

MICOM cung cp 5 vng bo v cho s c chm t c th hin trong mch vngtng tr t gic c trng hnh 5.9.

S c th bo v c tt c cc s c chm t xy ra trong vng bo v v cngc xem nh mt phn ca cc s c pha.

i vi s c chm t, dng in d bt ngun t tng vct dng in u vo (Ia +Ib + Ic) c gi tng chy qua mch vng s c pha - t. V vy, mch vng s cca bt k vng no cng phi c m rng h s nhn (1+kZ0) so snh vi thnh

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phn th t thun cho ph hp vi s c pha. KZ0 c gi l h s dng in d vc xc nh nh sau:

kZ0 = ((Z0 Z1) / 3Z1)

?kZ0=?(Z0 Z1) / 3.Z1 ()

Trong :

Z1: tng tr th t thun ca Z. Z0: tng tr th t khng ca Z.

Tnh ton ci t cc vng cho rle khong cch s MICOM:

Mi vng khong cch c th c kch hot hoc khng s dng, ngha l chc nngca vng c th c kt ni tham gia bo v hoc khng c la chn. kchhot mt vng no th gi tr trong chn vng phi c chn l bit 1, cn bit 0nu khng dng vng . Ch rng vng 1 khong cch lun c kch hot.

Hnh 5.10

Tt c cc gi tr ci t vng u c tnh ton trong h ta cc Z?0 . Trong Zc tnh bng n v Ohm ( ) v 0 ().

Vng 1: Ca bo v khong cch nn c ci t sao cho c th bao ph c cngnhiu phn ng dy c bo v m cho php ct tc thi c chn lc vi tt c ccs c xy ra trong vng ny. Tng tr t vng 1 thng c xc nh bng khong(80 85)% tng tr ca on Z m n lm bo v chnh. i vi rle khong cch sMICOM, gi tr tng tr t vng 1 c xc nh theo cng thc:

Zs(I) = 0,8.ZAB( ) (4-80a)

Zth (I) = Zs

(I).NctNvt

( ) (4-80b)

Vi: Nct, Nvt ln lt l t s bin ca bin dng v bin in p.

Vng 1 khong cch l vng tc ng chn lc tuyt i nn thi gian t vng 1 c thchn bng 0 (sec).

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Vng 2: Gi tr tng tr t vng 2 nn ci t sao cho c th bao ph 20% on cuiZ cn li khng c bao ph bi vng 1 v ton b phn thanh gp trm lin k mkhi ngn mch ti , bo v khong cch trm ny khng th tc ng. Thng thng n gin, ngi ta c th ly gi tr t ca vng 2 khong 120% gi tr tng tr caon ng dy c bo v. c th ct nhanh mi s c xy ra trong vng 2, c thdng cc s ct lin ng v khi vng 2 c th c m rng cng ln cng tt.Tuy nhin vng 2 khng c vt ra ngoi vng 1 ca bo v khong cch on Zlin k, iu ny l cn thit c th m bo c s phi hp c chn lc vi thigian vng 2 ca bo v ca bo v lin k. y chnh l l do m vng 2 bo v khongcch nn ci t bao ph di 50% tng tr on Z ngn nht ca on Z lin k.Gi tr tng tr vng 2 c th tnh theo cng thc:

Zs(II) = ZAB + 0,3.ZBC( ) (4-81a)

Zth (II) = Zs

(II).NctNvt

( ) (4-81b)

Thi gian t vng 2 ca bo v c phi hp vi thi gian ct ca vng 1 Z lin k.Thi gian tr nh nht ca vng 2 c th ly bng 200 msec. Thi gian ny phi ciu chnh khi yu cu phi phn cp vi vng 2 ca bo v khc hoc phi hp bov d phng cho bo v ca on lin k. Thng thng thi gian t cp 2 ca cc bov khong cch t ti cc TBA A,B,C l nh nhau v c xc nh theo cng thc:

tnII = t(n + 1)

I + t (4-82)

Trong :

t(n + 1)I thi gian t cp 1 ca bo v on lin k cn phi hp.

t: bc chn la thi gian, thng t = 0,5 sec.

* Vng 3: Thng c dng lm nhim v bo v d tr cho vng 1, vng 2 v bov khong cch ca on Z lin k, trn thc t n gin ngi ta thng tnh gitr tng tr t vng 3 ca bo v khong cch bao trm 120% tng tr ca Z di nhtlin k. iu ny cho php rle khong cch t ti TBA A c th ct c cc ngnmch trn Z lin k khi ton b cc bo v ca on ny khng lm vic. Tng tr tvng 3 c xc nh theo cng thc:

ZsIII = (ZAB + ZBC).1,2 (4-83a)

Zth III = Zs

III.NctNvt

( ) (4-84b)

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Thi gian t vng 3 c phi hp vi thi gian t vng 2 ca bo v on lin k.Thi gian tc ng nh nht vng 3 ca rle khong cch MICOM c th t n 400msec

Vng P: L vng kh trnh, vic tnh ton ci t cho vng P ph thuc vo cc ngdng c th ca n. Cc ng dng vng P y c th s dng nh mt bo v d phnghng ngc cho thanh ci v MBA, cng c th s dng vng P hng thun tngs vng ca bo v. Vng P cng c th hu ch cho cc trng hp tng h trong bov Z kp.

Vng 4: L vng hng ngc, thng c s dng lm bo v cho thanh ci TBA.Khi tng tr vng 4 c th ci t n 25% tng tr vng 1ca rle pha hng ngccho Z ngn (

vi DAB,DAC, DBC l khong cch gia cc pha AB,AC,BC.

Bng di y cho cc gi tr in tr Rhq tng ng vi dng s c nh nht i vicc s c pha-pha tng ng vi cc cp in p khc nhau:

Khong cch cch in (m) in p h thng (kV) If = 1 kA If = 5 kA If = 10kA

2 33 3,6 ( ) 0,4 ( ) 0,2 ( )

5 110 9,1 ( ) 1,0 ( ) 0,4 ( )

8 220 14,5 ( ) 1,5 ( ) 0,6 ( )

If:dng ngn mch nh nht khi xy ra s c pha-pha.

Tnh ton gi tr in tr t cho s c chm t:

in tr ci t ca rle cho s c chm t (RG) nn tho mn cc yu cu i hi cain tr s c, nhng trnh thao tc khi tr khng ti l nh nht. in tr s c baogm in tr h quang v in tr c nh. Ngoi ra, tt nht in tr bt k vng noca rle, thng thng khng nn ln hn 10 ln in tr mch vng t.

Ni chung gi tr in tr ny nn ly khong 40 tnh theo pha s cp h thng. ivi trng hp in tr chm t ln, tnh hung ny c th xut hin ni khng c phnt khong cch no c th tc ng. Trong trng hp ny phi s dng cc thit b bov s c chm t b sung.

Cc s bo v khong cch:

Cc s c bn ca rle khong cch s MICOM:

Cc s bo v khong cch c bn ph hp cho cc ng dng m khng i his dng knh tin. Mt cch tng qut, vng 1 v 2 cung cp chc nng bo v chnh nhtrong hnh 5.11cn vng 3 ng vai tr bo v d phng.

Bo v chnh trong s c bn (Hnh 5.11)

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Trn hnh 5.12 trnh by s ct logic c bn ca rle khong cch s MICOM. Ch rng, vi rle khong cch s P441, P442 v P444, cc b thi gian vng t tZ1 ntZ4 hot ng c lp nhau v cng bt u tnh thi gian k t khi s c c tm thy.iu ny gii thch ti sao chng c a vo song song nhau trong s logic.

S ct logic c bn (Hnh 5.12)

Cc du nhy s dng trong s (v d Z1' ) ch ra rng cc vng bo v c lm n

nh trnh tc ng xu ca dng t ho my bin p. Phng php c s dng tc tin cy v kh nng d tm thnh phn sng hi bc hai.

S c bn hp nht cc cc c tnh sau:

Vng 1 cho php ct tc thi, cng c th chn thi gian tr t (0 10) sec.

Thi gian ct tr vng 2, 3, 4 v P cng c th ci t t (0 10) sec.

S khong cch c bn trn thng thch hp cho cc Z n hoc kp c mt ngunhay hai ngun cung cp. Hn ch ca s c bn ny l khi xy ra s c cui Z(khong 20% chiu di on cui Z bo v), thi gian ct s c tng ln n thi gianct vng 2. Thi gian ny c th c ci thin nu s dng s vng 1 m rng.

S vng 1 m rng:

S vng 1 m rng (zone 1 extension) c th ng dng cho cc xut tuyn hnh tia cung cp bo v tc cao cho ton b on Z c bo v. Trn hnh 5.13 trnhby tng tr vng 1 m rng so vi vng 1.

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Trong vng ny vng 1X c kch hot v ci t n phn vt vng ca Z cbo v. Vng 1X thng c s dng kt hp vi TL c th ct nhanh cc s cv nng cao tin cy cung cp in ca h thng in.

S vng 1 m rng (Hnh 5.13)

Cc s ct lin ng:

Cc s khong cch s dng truyn ct tn hiu cho php c th c chn la bicc s tiu chun sau:

Cc s truyn ct lin ng do phn t ni tuyn truyn tn hiu cho php(PUTT): s pup z2 (Permission underreaching protection Zone 2) v pupfwd (Fwd: Forward fault detection).

Cc s truyn ct lin ng do phn t vt tuyn truyn tn hiu cho php:s pop z2 v pop z1.

S logic ngun yu do phn t vt vng truyn tn hiu cho php. S logic gii kho. S kho bop z2 (Blocking overreaching protection zone Z2) v bop z1. S logic o dng.

S ct lin ng do phn t ni tuyn truyn tn hiu cho php (PUTT):s pup Z2:

cung cp kh nng loi tr mt cch nhanh nht tt c cc s c, c s c thong quav s c duy tr dc theo chiu di ca mch ng dy c bo v cn phi s dngs truyn tn hiu cho php. Trong s lin ng do phn t ni tuyn truyntn hiu cho php l s n gin nht c tch hp trong rle khong cch sp441, p442 v p444 ca alstom. Knh truyn cho s pup s dng tn hiu cho phpdo phn t ni tuyn pht ra. Trn hnh 5.14 trnh by s vng 1, vng 2 v trn hnh5.15 trnh by s logic ct lin ng. Nguyn l lm vic ca s nh sau: gi skhi ngn mch xy ra ti n1, im ngn mch ny thuc vng 2 ca bo v khong ccht ti a v thuc vng 1 ca bo v khong cch t ti b. Bo v khong cch ti b stc ng ct my ct ti b ng thi gi tn hiu cho php n b phn thu tn hiu bov a, b d tm s c ti a cng pht hin ra s c v ct my ct ti a, thi gian loitr hon ton s c ny nh hn rt nhiu so vi thi gian t vng 2. Nh vy s cs c loi tr vi thi gian nhanh nht c th, thi gian ny ph thuc vo thi gian

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truyn tn hiu lin ng gia hai bo v t hai u z v thi gian tr ca bo vcng vi thi gian tr ca my ct.

S phi hp vng 1 v vng 2 (Hnh 5.14)

u im ca s loi ny l:

Ch s dng knh truyn truyn tn hiu n cng nn chi ph cho knh truyntng i thp.

S cho php ct vi tin cy tng i cao vi cc s c trong vng bov.

Thi gian loi tr s c cui Z (khong 20% chiu di on cui Z ) khnhanh.

S logic ct lin ng PUP Z2 (Hnh 5.15 )

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Tuy nhin, nu ngn mch c dng tng i b m b d tm s c pha b A khngpht hin c hoc knh truyn tin b s c th bo v pha A (hnh 5.15) cng s khngtc ng.

S ct lin ng do phn t vt tuyn truyn tn hiu cho php (POTT) POP Z2:

y l dng s bin th th hai ca h rle P44X, s ny c mt s tnh cht vyu cu sau:

S i hi dng knh truyn tin kiu song cng ngn nga rle c th tcng nhm.

S POP Z2 thng c s dng tt hn i vi Z c chiu di ngn m gi tr in tr s c bin ng mnh v vng 2 bao ph ln hn vng 1.

Logic dng in o ngc c s dng ngn nga ct sai Z c bo vdo tc cao ca dng in ngc xut hin khi s c m mt nhnh ca mchZ kp va c ct ra.

S logic POP Z2 (Hnh 5.16) Nu knh tin b s c, khi s bo v khong cch c bn s tc ng.

Hnh 5.16trnh by hnh thc n gin ca s logic. S POP Z2 cng cth c s dng cho vng 4 hng ngc ca rle nh mt b d tm s chng ngc. iu ny c dng trong logic dng in o v trong c tnhphn hi ngun yu.

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S kho lin ng vi vng 2:

Khc vi s dng tn hiu cho php, loi s ny dng tn hiu kho truyn n bphn thu tn hiu ca rle pha i din khi pht hin s c vng ngc (vng 4 hngngc), iu ny s cho php ct nhanh cc s c cui Z. S c cc c im sau:

S kho lin ng ch yu cu knh truyn tn hiu n cng nn chi ph choknh truyn s gim i.

Vng 4 hng ngc c s dng gi tn hiu kho n rle pha i din trnh ct nhm.

Khi knh truyn n cng c s dng, s BOP c th d dng ng dngcc thit b u cui.

S d dng s dng h thng ti ba (PLC) truyn tn hiu kho. C th ct nhanh chng cc ngun cng sut ln pha cui Z.

Bo v chnh trong s BOP Z2 (Hnh 5.17)

S khi logic BOP Z2 (Hnh 5.18)

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Nu knh truyn b s c th rle khong cch s lm vic nh mt bo vkhong cch thng thng.

Tnh ton thng s ci t rle khong cch micom cho xut tuyn 220kv nng-hu (tba 500kv nng-tba 220kv hu)

Cc s liu h thng:

Chiu di on ng dy (line length):

nng - Hu: l = 97,72 Km.

Hu - ng hi: l = 170 Km.

Tng tr ng dy nng - Hu - ng hi (line impendances):

Tng tr th t thun (Positive sequence impendance):

Z1 = 0,0252?800 ( /Km).

Tng tr th t khng (zero sequence impendance):

Z0 = 0,877?820 ( /Km).

Tng tr MBATN AT4 ti TBA 220 HU:

ZB = 0,5 + 48,6 = 48,6025? 7,90 ( ).

T s bin dng in (current transformer ratio): Nct = 1200/1 (A) T s bin dng in (voltage transformer ratio): Nvt =(220.000/110)

Cc gi thit ban u:

Trong thc t khng phi lc no ngi ta cng s dng tt c cc vng ca rle khongcch s bo v m vic ci t vng no tc ng v vng no b kho cn ph thucvo tng trng hp c th nh: v tr ca bo v trong h thng, mc bin ng caph ti, cng sut ca h thng..., thng thng Vit Nam cc rle khong cch sc s dng nh mt bo v khong cch ba cp. Ngha l: vng 1, vng 2, vng 3c ci t thc hin cc chc nng bo v cn cn vng 4, vng P thng c sdng thu thp cc thng s bin ng ca h thng phc v cho cng tc iu .

Trn tnh thn , y chng ta gi thit rng vng 1 m rng (zone 1 extension), vngkh trnh P (zone programmable), vng 4 khng s dng v ch s dng ba vng hngthun.

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Cc gi tr ci t cho rle khong cch s micom c tnh ton qui i v gi tr scp.

Gc pha Z ci t cho rle t -900 n +900, bc nhy l 10.

Tnh ton chi tit:

Gi tr tng tr ton b ng dy tnh gi tr s cp:

on nng - Hu:

Z1s = 0,252?800.97. 72=24 ,62?800

= 4,275 + 24,244 ( ).

on Hu - ng hi:

Z1s = 0,252?800. 170=42 ,84?800 ( ).

Cc gi ti ci t pha vng 1:

Vng 1 c yu cu phi bo v khong 85% chiu di ng dy gia TBA 500 kV NNG v TBA 220 kV hu.

Zs = 0,85.24,62?800 = 20,927?800 ( )

Gi tr t vng 1: 20,927 ( ). Gc pha: 80 ().

Cc gi tr ci t pha vng 2:

Vng 2 yu cu phi bo v c khong 20% on ng dy cn li m vng 1 khngvi ti v phi bao trm hon ton thanh ci TBA 220 kV HU cng vi khong 30%chiu di on Z Hu - ng hi.

Zs = 24,62?800 + 0,3.42,84?800 = 37,477?800 ( )

gi tr t thc s ca cng 2: 37,477 ( ). Gc pha: 80 ().

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Cc gi tr t vng 3:

Vng 3 y yu cu ngoi bo v d tr cho vng 1, vng 2 ca bo v khong ccht ti TBA 500 kV NNG cn bo v d tr cho bo v khong cch ti TBA 220kV Hu. Gi tr tng tr t vng 3 c xc nh bng 120% chiu di Z nng -Hu - ng hi.

Zs = (24,62?800 + 42,84?800).1,2 = 4,775+j72, 846=73 ?86,265 ( )

Gi tr t thc s vng 3: 73 ( ). Gc pha: 87 ().

Rle khoang cach Micom P44X

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Rle khoang cach Micom P44XRle khoang cach Micom P44XGii thiu chung v rle khong cch s micom P44XCu hnh chung ca rle khong cch s MICOM:Cc li ch ca vic s dng rle khong cch s MICOM:

Cc ng dng ca rle khong cch s Micom h P44xChc nng bo v khong cch:Bo v khong cch cho s c pha:Bo v khong cch cho s c chm t:Tnh ton ci t cc vng cho rle khong cch s MICOM:

Cc s bo v khong cch:Cc s c bn ca rle khong cch s MICOM:S vng 1 m rng:

Cc s ct lin ng:S ct lin ng do phn t ni tuyn truyn tn hiu cho php (PUTT):s pup Z2:S ct lin ng do phn t vt tuyn truyn tn hiu cho php (POTT) POP Z2:S kho lin ng vi vng 2:

Tnh ton thng s ci t rle khong cch micom cho xut tuyn 220kv nng-hu (tba 500kv nng-tba 220kv hu)Cc s liu h thng:Cc gi thit ban u:Tnh ton chi tit:Gi tr tng tr ton b ng dy tnh gi tr s cp:Cc gi ti ci t pha vng 1:Cc gi tr ci t pha vng 2:Cc gi tr t vng 3: