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n Mn Hc Mng Li in

Hunh Trung Thnh- Page 1

M U Ngy nay, in nng l mt phn v cng quan tr ng trong h thng nng l ng

ca mt quc gia.in nng l mt dng nng l ng c nhiu u im nh: ddnh

chuyn thnh cc dng nng l ng khc (nhit, c, ha), dtruyn ti v phn phi.Chnh v vy in nng c s dng r t r ng ri trong mi lnh vc hot ng cacon ng i. Trong iu kin n c ta hin nay ang trong th i k cng nghi p ho vhin i ho th in nng li ng mt vai tr v cng quan tr ng.

in nng l ngun nng l ng chnh ca cc ngnh cng nghip, l iu kinquan tr ng pht trin cc th v dn c.. V l do khi l p k hoch pht trinkinh tx hi, k hoch pht trin in nng phi i tr c mt b c, nhm tha mnnhu cu in nng khng nhng trong giai on tr c mt m cn dkin cho sphttrin trong tng lai 5,10 nm hoc c khi cn lu hn na. Thm vo nn kinh t nc ta cn trong giai on ang pht trin v vic sn xut in nng cn ang thiuthn so v i nhu cu tiu th in nn vic truyn ti in, cung cp in cng nh phn phi in cho cc h tiu thcn phi c tnh ton k lng va m boh p l v k thut cng nh vkinh t.

Trong qu trnh nghin cu v thit k n mn hc ny a ra phng n ckh nng thc thi nht trong vic thit k mng li in cho mt khu vc gm cc h tiu th in loi I. Nhn chung, phng n c a ra p ng c nhng yucu c bn ca mt mng l i cung c p in nh: tin cy cung cp in, cht l ngin nng, tnh kinh t v an ton

D cgng nhng n skhng trnh khi nhng thiu st v hn ch, em r tmong nhn c sch bo v gip ca cc thy em c thhon thin c nidung thit k n, hon thin v nng cao kin thc chuyn mn cng nh rn luyn bn thn vtc phong lm vic, tinh thn v trch nhim.

Em xin chn thnh cm n sgi p ca Thy Phm Nng Vn gip emhon thnh n mn hc ny.

TPHCM, ngy 4 thng 4nm 2013

Sinh vin thit k

Hunh Trung Thnh


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MC LC M U.1

CHNG 15

PHN TCH NGU N V PHTI.5

CN B NG CNG SUT TRONG HTHNG I N.5

1.1 PHN TCH NGU N V PHTI .............................................................................. 5 1.1.1 Ngun in ........................................................................................................... 5 1.1.2 Phti in ........................................................................................................... 5

1.2 CN B NG CNG SUT TC D NG ........................................................................ 5 1.3 CN B NG CNG SUT PH N KHNG .................................................................. 6 1.4 CC SLIU K THUT C B N ............................................................................ 8

1.4.1 Khong cch tnh my t i cc phti .............................................................. 8 1.4.2 Bng thng sca cc phti in ...................................................................... 9 1.4.3 Cc la chn k thut ban u ............................................................................. 9

CHNG 2..10

LP PHNG N V TNH TON KTHUT CC PHNG N..10

2.1 T VN ................................................................................................................ 10 2.2 D KIN CC PHNG N CUNG CP I N V CC TIU CHU N TNHTON K THUT .............................................................................................................. 10

2.2.1 Cc phng n ni dy ....................................................................................... 11 2.2.2 Tiu chun k thut ca phng n.................................................................... 13 2.2.3 Phn bcng sut trong mng in .................................................................... 13 2.2.4 Chn in p nh mc ca mng in .............................................................. 14

2.2.5

Chn tit din dy dn ........................................................................................ 14

2.2.6 Xc nh cc thng sca ng dy ................................................................ 15 2.2.7 Xc nh tn tht in p l n nht ca phng n............................................. 15

2.3 TNH TON K THUT PHNG N 1.................................................................. 16 2.3.1 Chn in p nh mc ca mng in .............................................................. 17 2.3.2 Xc nh tit din dy dn v cc thng sca ng dy ................................ 17 2.3.3 Xc nh tn tht in p l n nht ca phng n............................................. 19

2.4 TNH TON K THUT PHNG N 2.................................................................. 20 2.4.1 Chn in p nh mc ca mng in .............................................................. 20 2.4.2 Xcnh tit din dy dn v cc thng sca ng dy ................................ 21 2.4.3 Xc nh tn tht in p l n nht ca phng n............................................. 22

2.5 TNH TON K THUT PHNG N 3.................................................................. 23 2.5.1 chn in p nh mc ca mng in ............................................................... 23 2.5.2 Xc nh tit din dy dn v cc thng sca ng dy ................................ 23 2.5.3 Xc nh tn tht in p l n nht ca phng n............................................. 25

2.6 TNH TON K THUT PHNG N 4.................................................................. 26 2.6.1 Chn in pnh mc ca mng in .............................................................. 26 2.6.2 Xc nh tit din dy dn v cc thng sca ng dy ................................ 26 2.6.3 Xc nh tn tht in p l n nht ca phng n............................................. 28

2.7 TNH TON K THUT PHNG N 5.................................................................. 29 2.7.1 Phn bcng sut trong mng in .................................................................... 29 2.7.2 Chn in p nh mc ca mng in .............................................................. 31 2.7.3 Xc nh tit din dy dn v cc thng sca ng dy ................................ 32 2.7.4 Xc nh tn tht in p l n nht ca phng n............................................. 33


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CHNG 3..35

SO SNH KINH T CC PHNG N...35

3.1 PHNG PHP SOSNH KINH T......................................................................... 35 3.2 TNH TON VKINH T CHO CC PHNG N................................................ 36

3.2.1

Phng n 1........................................................................................................ 36

3.2.2 Phng n 2........................................................................................................ 37 3.2.3 Phng n 3........................................................................................................ 37 3.2.4 Ph ng n 4 ........................................................Error! Bookmark not defined.

3.3 L A CHN PHNG N HP L NHT ............................................................... 38 CHNG 4..39

CH N MY BIN P V S NI I N..39

4.1 CH N S L NG V CNG SUT CC MY BI N P TRONG CC TR MHP .................................................................................................................................. 39

4.1.1 Phti I.............................................................................................................. 40

4.1.2 Phti II ............................................................................................................. 40 4.1.3 Phti III ............................................................................................................ 40 4.1.4 Phti IV ............................................................................................................ 40 4.1.5 Phti V ............................................................................................................. 40 4.1.6 Phti VI ............................................................................................................ 41 4.1.7 Thng scc my bin p .................................................................................. 41

4.2 CHN S NI DY TR M HP ..................................................................... 41 4.2.1 Tr m ngun ....................................................................................................... 41 4.2.2 Tr m trung gian ................................................................................................. 42 4.2.3 Tr m cui............................................................................................................ 42 4.2.4 S ni dy chi tit li in .......................................................................... 44

CHNG 5..45 TNH TON PHN BCNG SUT TRONG MNG I N TNH TON CH XCLP CA MNG I N..45

5.1 TNH TON CHI TIT S PHN BCNG SUT TRONG MNG I N .... 45 5.1.1 Ch phti cc i ........................................................................................ 45 5.1.2 Ch phti cc tiu ....................................................................................... 49 5.1.3 Ch sc....................................................................................................... 54

5.2 TNH TON IN P TI CC IM N T C MNG IN..................... 58 5.2.1 Ch ph ti cc i....................................................................................... 58

5.2.2 Ch ph ti cc tiu...................................................................................... 59 5.2.3 Ch sau s c................................................................................................. 60 CHNG 6..61

IU CHNH I N P TRONG HTHNG I N61

6.1 YU CU IU CHNH IN P TH NG...................................................... 61 6.2 YU CU IU CHNH IN P KHC TH NG ......................................... 64

CHNG 7..70

CC CH TIU KINH T K THUT C MNG IN.70

7.1 VN U T XY D NG MNG I N ........................................................... 70 7.2 T N THT CNG SUT TC D NG TRONG MNG I N .......................... 70 7.3 T N THT IN NNG TRONG MNG I N ................................................. 70


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7.4 TNH CHI PH GI THNH .................................................................................. 71 7.4.1 Chi ph vn hnh hng nm................................................................................ 71 7.4.2 Chi ph tnh ton hng nm................................................................................ 72 7.4.3 Gi thnh truyn ti in nng............................................................................ 72 7.4.4 Gi thnh xy dng 1 MW cng sut phti trong ch cc i ................... 72


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CHNG 1 PHN TCH NGUN V PH TI

CN BNG CNG SUT TRONG H THNG IN 1.1PHN TCH NGUN V PH TI

1.1.1 Ngun in V i githit khi thit k mng in l c mt ngun cung cp in nh sau:

Ngun in tnh t thanh gp cao p ca Nh My in, tr m trung gian a phng.

Ngun in cung cp cng sut tc dng cho phti. H s cng sut trn thanh gp (c gi i hn cng sut phn khng)

ndcos 0,85 .1.1.2 Ph ti in

V i githit vphti in nh sau:

Cng sut ca phti c 32MW (kh nng ti ca ng dy 110kV). Hscng sut ca phti l 0,9. tin cy cung cp in l c 6 hloi I . Th i gian sdng cng sut cc i l = 4800h Hs ng th i m=1. in p danh nh ca l i thc p l 10kV.

1.2CN BNG CNG SUT TC DNG Ti mi thi im lun c scn bng gia in nng sn xut ra v in nng tiu

th, iu cng c ngha l ti mi thi im cn phi c scn bng gia cng suttc dng v cng sut phn khng ra v i cng sut tc dng v cng sut phn khngtiu th. Nu s cn bng trn b ph v th cc ch tiu cht lng in b gim, dnn gim cht l ng ca cc sn phm hoc c thmt n nh hoc lm tan r h thng.

Cng sut tc dng ca cc ph ti lin quan t i tn sca dng in xoay chiu.Tn strong hthng s thay i khi scn bng cng sut tc dng trong hthng b ph v . Gim cng sut tc dng pht ra dn n gim tn s v ng c li. V vy timi thi im trong cc ch xc l p ca hthng in, cc nh my in trong h thng cn phi pht cng sut bng tng cng sut ca cc h tiu th, k ctn thtcng sut trong hthng.

Cn bng s bcng sut tc dng c thc hin trong ch phti cc i cahthng. phng trnh cn bng cng sut tc dng c dng tng qut sau:


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nd ycP = P Trong :

ndP : Cng sut tc dng pht ra ca ngun.

ycP : Cng sut tc dng yu cu ca phti.

m:

yc pt md td dtP =m P + P + P + P .v i:

m : Hs ng th i, y m=1.

ptP : Tng cng sut tc dng trong ch cc i.

ptP = P1+ P2 +P3 +P4 +P5 +P6=20+24+26+30+32+20=152 MW.

mdP : Tng tn tht cng sut tc dng trn ng dy v trong tr m bin p,

c ly bng 5% ptP

MW.tdP : Tng cng sut tdng ca nh my in, y tdP =0.

(do ch xt t thanh gp cao p ca nh my in hay tr m bin p a phng).

dtP : Tng cng sut d tr ca mng in ( y ta coi hthng c cng

sut v cng l n nn dtP =0).

Vy:

nd ycP = P

=152+7,6=159,6 MW.

Do githit ngun cung cp cng sut tc dng nn ta khng cn bng chng.

1.3CN BNG CNG SUT PHN KHNG m bo cht lng in p cn thit cc h tiu th trong hthng in v

trong cc khu vc ring bit ca n, cn c y cng sut ca cc ngun cng sut phn khng. V vy trong giai on u ca thit k pht trin hthng in hay ccmng in ca cc vng ring bit cn phi tin hnh cn bng s bcng sut phnkhng ca li in.


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Cn bng cng sut phn khng trong mng in thit k c ting hnh chungi v i chthng.

Cn bng cng sut phn khng c tin hnh i v i ch cc i ca hthngin v phng trnh cn bng trong tr ng h p ny c dng:

nd ycQ = Q (c thc thm b cng sut phn khng).6

nd b pti mba L Ci 1

Q Q m. Q Q Q Q

Trong :

ndQ : tng cng sut phn khng ca cc my pht trong cc nh my in.

bQ : cng sut ca cc thit b b.

ptiQ : cng sut phn khng ca cc phti.

mbaQ : tn tht cng sut phn khng ca cc my bin p.

CQ : cng sut phn khng sinh ra bi dung khng ng dy.

LQ : tn tht cng sut phn khng cm khng ng dy.

(v i githit td dtQ 0,Q 0 ).

Kim tra biu thc trn ta c:nd nd ndQ =tg P (Vi nd ndcos =0,85 tg =0,6197 ).ndQ =0,6197.159,6=98,9 MVAr.

ycQ : Tng cng sut phn khng yu cu ca ph ti.

M:

6

yc pti mba L Ci 1

Q m. Q Q Q Q .

Vi

m: l h s ng thi m=1.

6

ptii 1

Q : Tng cng sut phn khng ca ph ti ch cc i.


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n Mn Hc Mng Li in


6

ptii 1

Q = Q1+ Q2 + Q3 + Q4 + Q5 + Q6

M:

Qi =P i .tg i ( cos i =0,9 tg i =0,484) do ta c bngsau:

Ph ti 1 Ph ti 2 Ph ti 3 Ph ti 4 Ph ti 5 Ph ti 6

Pi(MW) 20 24 26 30 32 20

Qi(MWr) 9,68 11,61 12,584 14,52 15,48 9.68

Bng 1.1Do :

ptQ =73,47 MVAr.

BAQ : Tng tn tht cng sut phn khng trong cc tr m h p c tnh

bng 15% ptQ ,ta c:

MVAr

L CQ , Q : Tng gm: tn tht cng sut phn khng trn ng dy vcng sut phn khng do dung dn do ng dy sinh ra. Gis ng dy truyn ticng sut t nhin v ng dy khng tn tht (R=0,G=0). Vy L CQ Q .

td dtQ Q : Tng cng sut t dng v d tr ca nh my, trongtr ng h p ny chng bng 0.

ycQ =73,47+11,02=84,49 MVAr

Ta thy ycQ < ndQ nn chng ta khng phi tin hnh b s b.

1.4CC S LIU K THUT C BN

1.4.1 Khong cch t nh my ti cc ph ti T s mt bng nh my ta c khong cch t nh my n phti l:


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on N-1 N-2 N-3 N-4 N-5 N-6

l(km) 40 50 70 28,28 58,3 80,62Bng 1.2

1.4.2 Bng thng s ca cc ph ti in Nh vy ta c bng cc thng sca cc phti thit nh sau:

Ph ti Ln-i(km) Pi(MW) Qi(MVAr)

1 40 20 9,68

2 50 24 11,61

3 70 26 12,58

4 28,28 30 14,52

5 58,30 32 15,48

6 80.62 20 9,68Bng 1.3

1.4.3 Cc la chn k thut ban u - Truyn ti in xoay chiu AC.- Dng ng dy trn khng dy dn tr n.

- Dng dy nhm li thp AC.

- Dng ct b tng ct thp v i hsvn hnh ng dy vhda 0,04

K hiu dy dn AC-70 AC-95 AC-120 AC-150 AC-185 AC-240

Ct b tng ly tm 300 308 320 336 352 402Ctthp 380 385 392 403 416 436

Bng 1.4

Gi thnh ng dy trn khng mt mch in p 110kV ( 610 /km).

Ghi ch: Gi thnh ng dy hai mch bng 1,6 ln gi thnh ng dy mtmch.

- Gi thnh tr m bin p truyn ti c mt my bin p in p 110/10 kV v i hs vn hnh cc thit b trong tr m bin p vha =0,10.


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Cng sut nh mc, MV 16 25 32

Gi thnh, 910 /trm 15,000 22,000 29,000

Bng 1.5Ghi ch: Gi thnh tr m hai my bin p bng 1,8 ln gi thnh tr m c mt my

bin p.

CHNG 2 LP PHNG N V TNH TON K THUT CC

PHNG N 2.1T VN

Thit k li in l mt bi ton nhca bi ton quy hoch li in. Cc ch tiu vkinh t- k thut ca mng in phthuc r t nhiu vo s ca n. V vycc s mng in cn c chn sao cho c chi ph nhnht, m bo tin cycung cp in cn thit, m bo cht lng in nng yu cu ca cc h tiu th,thun tin v an ton trong vn hnh, kh nng pht tr in trong tng lai v ti p nhncc phti m i.

Trong thit k hin nay, chn c s ti u ca mng in, ng i ta s dng phng php nhiu phng n. Tcc v tr cho ca cc phti, cn tin hnhdkin mt s phng n tt nht s c chn trn c s so snh ch tiu kinh t- k thut ca cc phng n. Mng in cn c tin cy cao, tnh kinh tv linh hot cnthit. Phng n ti u l phng n i tiu chun k thut v c chi ph kinh tnh nht.

2.2 D KIN CC PHNG N CUNG CP IN V CC TIUCHUN TNH TON K THUT

Ta c theo yu cu cung cp in cho 6 h loi I , m h loi mt l nhng h l nhng h tiu th in quan tr ng, nu nh ngng cung cp in c thgy nguyhim n tnh mng v sc kho con ng i, gy thit hi nhiu vkinh t, h hngthit b, lm hng hng lot sn phm, r i lon qu trnh cng nghphc tp. Do cc phng n cung c p cho cc h loi I phi c c p thai ngun.Vic la chncc phng n i dy ca mng in cn m bo cc yu cu chnh sau:

Cung cp in lin tc.

m bo cht lng in nng.

m bo tnh linh hot ca mng in.

m bo tnh kinh tv c kh nng pht trin trong tng lai.


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m bo an ton cho ng i v thit b.

i tphti gn ngun n phti xa ngun.

Cc mch vng c chiu di khng qu l n.

2.2.1 Cc phng n ni dy Da theo mt bng thit k v yu cu ca cc phti, ta a ra 6 phng n i

dy nh sau:

Hnh 2.1

Hnh 2.2


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Hnh 2.3

Hnh 2.4


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Hnh 2.5

2.2.2 Tiu chun k thut ca phng n Ta xt tiu chun k thut ca cc phng n cc chlm vic bnh th ng v ch

lm vic sau sc.Quy nh ti ch lm vic bnh thng th in p ti tt ccc nt trong mng

in: dm dm0,95U Ui 1,05U .

Ch sc(sc1 phn t) tiu chun N-1: dm dm0, 9U Ui 1,1U .

Trong qu trnh tnh ton thun tin ta quy nh tn tht in p l n nht v i h thng c 1 ngun in l tn tht in p tngun n im c in p th p nht trongmng in. Mc in p trong cc tr m hp c thch p nhn l ph h p nu trongcc ch ph ti cc i tn tht in p l n nht ca mng in mt cp in pkhng vt qu 10 n 15% trong ch lm vic bnh th ng, cn trong cc ch sc, tn tht in p l n nht khng vt qu 15 n 20%.

i v i mng kn phc t p, c thch p nhn tn tht in p l n nht 15 n 20%trong cc ch bnh thng v 20 n 25% trong cc ch sau s c. i v i cctn tht nh th, cn s dng cc my bin p iu chnh in p d i ti trong cctr m hp.

Khi thit k ta qui nh nh sau: max bt dmmax sc dm

U 10%U

U 20%U

2.2.3 Phn b cng sut trong mng in

Phn bcng sut trong mng in v i githit bqua tn tht cng sut (do chac tit din dy dn v cp in p).


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2.2.4 Chn in p nh mc ca mng in La chn ng in p ca ng dy ti in l mt vic r t quan tr ng lc thit

k h thng in v n cnh h ng tr c ti p t i tnh kinh tv k thut ca mngin. Gi tr in p nh mc ca mng in phthuc vo:

Khong cch truyn ti.

Cng sut truyn ti.

in p nh mc c trong mng in.Ta nu ra mt scp in p: 35kV, 110kV, 220kV.

Tnh chi ph kinh tca cc cp in p t tiu chun k thut.

Ly cp in p c hm chi ph tnh ton nhnht.

Da vo cng thc kinh nghim Still xc nh tr s in p nh mc ca mngin: U 4,34. L 16.P [kV,km,MW]

Trong : U l in p nh mc ca mng in.L l khong cch truyn ti.

P l cng sut truyn ti.

Ta tnh in p nh mc ca tng nhnh phti v ly cp in p chung.

Nu 70KV Ui 170KV th ta ly dmU 110kV .

2.2.5 Chn tit din dy dn Chn tit din dy dn l bi ton c bn nht khi thit k li in. C 3 phng

php chn tit din dy dn:

Chn tit din dy dn theo ch tiu kinh t.

Chn tit din dy dn theo iu kin pht nng.

Chn tit din dy dn theo iu kin tn tht in p cho php.Trong ni dung n mn hc li in ta chn tit din dy dn theo ch tiukinh t:

Mt kinh tca dng in.

D kin dng dy AC, ct b tng ct thp, ng dy 2 mch th chai mchc t trn cng mt ct, tbD 5m (i v i mng in 110KV).

Tra ph lc ti liu Thit k cc mng h thng in v i dy AC vta c 2ktJ 1,1A / mm .


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Dng in chy trn cc on ng dy c tnh theo cng thc:

lv max ii

kt

IF

J

max ilv max i

dm

SI

m. 3.U

Trong : i

F : tit din dy dn ( 2mm ).

lv max iI : dng nhnh cc i tnh trn lcn xc nh tit din (kA).

m: s l ng dy trn nhnh.

max lviS : cng sut truyn ti cc i trn ng dy ang xt.

ktJ : mt kinh tca dng in.

Tit din dy dn chn theo mt kinh t dng in phi tha mi cc iu kinsau:

Tha mn dng in lc sc.Tha mn iu kin tn tht in p cho php.

Dy dn c chn phi m bo bn v c hc.Tha mn iu kin vng quang.

Theo iu kin vng quang th tit din dy dn ca dy C nh sau:

i vi in p 110kV: 2minF 70mm .

i vi in p 220kV: 2minF 240mm .

2.2.6 Xc nh cc thng s ca ng dy 2.2.7 Xc nh tn tht in p ln nht ca phng n

Tn tht in p l n nht trong phng n hay trong mng in l tn tht in ptnh tngun n im c in p th p nht trong mng in.

Ch lm vic bnh th ng v i phti cc i

Tn tht in p c tnh theo cng thc: i i i ii 2dm

P.R Q .XU % .100

U

Trong :

Pi,Qi l cng sut tc dng v phn khng cc i trn nhnh i.Ri,Xi l gi tr in tr v in khng ca nhnh thi.

H tiu th loi I ta phi dng ng dy 2 mch nn in tr v in khng ca ng dy b gim i mt na.


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Ch sau sc Ti mt thi im ch xt mt sc, khng xt n scx p chng.

Vi ng dy hai mch khi xy ra scnng nnht ta githit r ng mt ngdy ca nhnh tr c ti p ni v i ngun b t. Do dy cn li phi ti mt l ngcng sut gp i so v i lc vn hnh bnh th ng v tn tht in p nhnh sv cng tng ln gp i.

Cc phng n phi tha mn iu kin vtn tht in p sau m i c th dng so snh vmt kinh tl:

Lc vn hnh bnh th ng: U% 10 %.Lc xy ra sc: scmaxU % = 20%.

2.3TNH TON K THUT PHNG N 1

Hnh 2.7


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2.3.1 Chn in p nh mc ca mng in

Da vo cng thc kinh nghim Still tnh ton cho tng l ng dy ta c bngsliu sau:

L N-1 N-2 1-3 N-4 N-5 N-6

L(km) 40,000 50,000 30,000 28,280 58,300 80,620

Pmax 46,000 24,000 26,000 30,000 32,000 20,000

Qmax 22,264 11,610 12,584 14,520 15,480 9,680

Smax 51,102 26,660 28,885 33,329 35,547 22,219

Ui(kV) 123,405 92,2887 93,555 99,8746 105,7926 88,66863Bng 2.1

Vy ta chn in p nh mc cho mng in l: dmU =110kV.

2.3.2 Xc nh tit din dy dn v cc thng s ca ng dy Ta chn tit din theo phng php mt kinh tca dng in ly tit din dy

dn tiu chun gn nht. Sau tra bng phlc ta c cc thng sca dy dn .K t qu c ghi trong bng sliu sau:


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L N-1 N-2 1-3 N-4 N-5 N-6

S mch 2 2 2 2 2 2

Pi(MW) 46,000 24,000 26,000 30,000 32,000 20,000Qi(MVAr) 22,264 11,610 12,584 14,520 15,480 9,680

S(MVA) 51,102 26,660 28,885 33,329 35,547 22,219

Ii(A) 134,226 70,047 75,893 87,569 93,397 58,378

Fi(mm2) 122,060 63,679 68,993 79,608 84,906 53,070

DD chn AC-120 AC-70 AC-70 AC-70 AC-95 AC-70

Li(km) 40,000 50,000 30,000 28,280 58,300 80,62

r 0( /km) 0,270 0,460 0,460 0,460 0,330 0,460

x0( /km) 0,423 0,440 0,440 0,440 0,429 0,440

b0(10-6S/km) 2,690 2,580 2,580 2,580 2,650 2,580

R( ) 10,080 11,500 6,900 6,504 9,619 18,540

X( ) 16,920 11,000 6,600 6,221 12,505 17,736

B(10-6S) 215,520 258,000 154,800 145,924 308,990 415.991

Icp(A) 380,000 265,000 265,000 265,000 330,000 265,000Bng 2.2

Kim tra iu kin pht nng dy dn khi sc:

I sc N-1 = I 1 .2 = 134,226.2 = 268,452 A< I cp = 380 A

I sc N-2 = I 2 . .2 = 70,047.2 = 140,094 < I cp = 265 A

I sc 1-3 = I 3 .2 = 75,893 .2 = 1 51,786 A< I cp = 265 A

I sc N-4 = I 4 .2 = 87,569 .2 = 175,138 A< I cp = 265 A

I sc N-5 = I 5 .2 = 93,397 .2 = 186,794 A< I cp = 330 A

I sc N-6 = I 6 .2 = 58,378 .2 = 1 16,756 A< I cp = 265 A

Vy tit din dy dn chn tha mn iu kin pht nng khi sc.


19/74

n Mn Hc Mng Li in


2.3.3 Xc nh tn tht in p ln nht ca phng n

2.3.3.1 Ch lm vic bnh thng

L N-1 N-2 1-3 N-4 N-5 N-6

Smch 2 2 2 2 2 2

Ui(kV) 123,405 92,2887 93,555 99,8746 105,7926 88,6686

Uibt% 6,945 3,336 2,169 2,359 4,143 4,483Bng 2.3

Vy max btU %=9,114%

2.3.3.2 Ch lm vic sau s c

Vy max scU % 16,059%

Vy phng n 1 t yu cu k thut.


20/74

n Mn Hc Mng Li in



Hnh 2.8

2.4.1 Chn in p nh mc ca mng in

Da vo cng thc kinh nghim Still tnh ton cho tng l ng dy ta c bngsliu sau:

L N_1 N_2 1_3 N_4 4_5 N_6

L(km) 40,000 50,000 30,000 28,280 31,620 80,620

Pmax 46,000 24,000 26,000 62,000 32,000 20,000

Qmax 22,264 11,610 12,584 30,008 15,480 9,680

Smax 51,102 26,660 28,885 68,880 35,547 22,219

Ui(kV) 123,405 92,2887 93,555 141,502 103,288 88,66863Bng 2.4

Vy ta chn in p nh mc cho mng in l: dmU =110 kV.


21/74

n Mn Hc Mng Li in




L N_1 N_2 1_3 N_4 4_5 N_6

S mch 2 2 2 2 2 2

Pi(MW) 46,000 24,000 26,000 62,000 32,000 20,000

Qi(MVAr) 22,264 11,610 12,584 30,008 15,480 9,680

S(MVA) 51,102 26,660 28,885 68,876 35,547 22,219

Ii(A) 134,226 70,047 75,893 180,966 93,397 58,378

Fi(mm2) 122,060 63,679 68,993 164,514 84,906 53,070


Li(km) 40,000 50,000 30,000 28,280 58,300 80,62

r 0( /km) 0,270 0,460 0,460 0,210 0,330 0,460

x0( /km) 0,423 0,440 0,440 0,416 0,429 0,440

b0(10-6S/km) 2,690 2,580 2,580 2,740 2,650 2,580

R( ) 10,080 11,500 6,900 2,960 9,619 18,540

X( ) 16,920 11,000 6,600 5,882 12,505 17,736

B(10-6S) 215,520 258,000 154,800 154,974 308,990 415.991

Icp(A) 380,000 265,000 265,000 445,000 330,000 265,000Bng 2.5

Kim tra iu kin pht nng dy dn khi sc:I sc N-1 = I 1 .2 = 134,226.2 =268,452 A< I cp = 380 A

I sc N-2 = I 2. .2=70,047.2=140,094 < I cp = 265 A

I sc 1-3 = I 3 .2 = 75,893.2 = 151,786 A< I cp = 265 A

I sc N-4 = I 4 .2 = 180,966.2 = 361,932 A < I cp = 445A

I sc 4-5 = I 5 .2 = 93,397.2 = 186,794 A< I cp = 330 A


22/74


23/74

n Mn Hc Mng Li in



Hnh 2.9

2.5.1 chn in p nh mc ca mng in Da vo cng thc kinh nghim Still tnh ton cho tng l ng dy ta c bng

sliu sau:

L N_1 N_2 1_3 N_4 N_5 2_6L(km) 40,000 50,000 30,000 28,28 58,300 40,000

Pmax 46,000 44,000 26,000 30,000 32,000 20,000

Qmax 22,264 21,129 12,584 14,520 15,480 9,680

Smax 51,102 48,810 28,885 33,329 35,547 22,219

Ui(kV) 123,405 121,643 93,555 99,8746 105,7926 88,66863Bng 2.7





24/74


25/74

n Mn Hc Mng Li in


2.5.3 Xc nh tn tht in p ln nht ca phng n

2.5.3.1 Ch lm vic bnh thng

L N_1 N_2 1_3 N_4 N_5 2_6

L(km) 2 2 2 2 2 2

Ui(kV) 123,405 121,643 93,555 99,8746 105,7926 88,6686

Uibt% 6,945 8,602 2,169 2,359 4,143 4,483Bng 2.9

6,945+2,169=9,114%

8,602+4,483=13,085%sai

Vy 13,085%

2.5.3.2 Ch lm vic sau s c i v i mch lin thng ta ch xt scvi ng dy gn ngun:

6,945+2,169=16,059%

8,602+4,483=21,687%

Vy 21,687%>20%Em xem li k t qutnh nh

Vy phng n3khngt yu cu k thut.


26/74

n Mn Hc Mng Li in



Hnh 2.10

2.6.1 Chn in p nh mc ca mng in Da vo cng thc kinh nghim Still tnh ton cho tng l ng dy ta c bng

sliu sau:

Khng th c ng dy N-1 v N-3 i cng hnh lang tuyn nh em nu.

L N_1 N_2 N_3 N_4 N_5 5_6

L(km) 40,000 50,000 70,000 28,280 58,300 80,620

Pmax 20,000 24,000 26,000 30,000 32,000 20,000

Qmax 9,680 11,610 12,584 14,520 15,480 9,680

Smax 22,219 26,660 28,885 33,329 35,547 22,219

Ui(kV) 84,053 92,2887 97,661 99,8746 105,7926 88,66863Bng 2.10





27/74

n Mn Hc Mng Li in


L N-1 N_2 N_3 N_4 N-5 N_6

S mch 2 2 2 2 2 2

Pi(MW) 20,000 24,000 26,000 30,000 32,000 20,000Qi(MVAr) 9,680 11,610 12,584 14,520 15,480 9,680

S(MVA) 22,219 26,660 28,885 33,329 35,547 22,219

Ii(A) 58,378 70,047 75,893 87,569 93,397 58,378

Fi(mm2) 53,507 63,679 68,993 79,608 84,906 53,070


Li(km) 40,000 50,000 70,000 28,280 58,300 80,62

r 0( /km) 0,460 0,460 0,460 0,460 0,330 0,460

x0( /km) 0,440 0,440 0,440 0,440 0,429 0,440

b0(10-6S/km) 2,580 2,580 2,580 2,580 2,650 2,580

R( ) 18,400 11,500 16,100 6,504 9,619 18,540

X( ) 17,600 11,000 15,400 6,221 12,505 17,736

B(10-6S) 103,200 258,000 361,200 145,924 308,990 415.991

Icp(A) 265,000 265,000 265,000 265,000 330,000 265,000Bng 2.11

Kim tra iu kin pht nng dy dn khi sc:I sc N-1 = I 1 .2 =58,378.2 = 116,756 A< I cp = 265 A

I sc N-2 = I 2 .2=70,047.2=140,094A< I cp = 265 A

I sc N-3 = I 3 .2 = 75,893.2 = 151,786 A< I cp = 265 A

I sc N-4 = I 4 .2 = 87,569.2=175,138 A < I cp = 265 A

I sc N-5 = I 5 .2 = 93,397.2 = 186,794 A< I cp = 330 A

I sc N-6 = I 6 .2 = 58,378.2=116756A< I cp = 265 A



28/74

n Mn Hc Mng Li in


2.6.3 Xc nh tn tht in p ln nht ca phng n 2.6.3.1 Ch lm vic bnh thng

L N_1 N_2 N_3 N_4 N_5 N_6

L(km) 2 2 2 2 2 2

Ui(kV) 84,053 92,2887 97,661 99,8746 105,7926 88,6686

ibtU % 4,262 3,336 5,061 2,359 4,143 4,483Bng 2.12

Vy

2.6.3.2 Ch lm vic sau s c 8,524%

Vy max scU % 10,122%

i v i mch lin thng ta ch xt scvi ng dy gn ngun

Vy phng n 4 t yu cu k thut.


29/74

n Mn Hc Mng Li in



Hnh 2.11

2.7.1 Phn b cng sut trong mng in

Ph ti Li(km) Pi(MW) Qi(MVAr)

1 40 20 9.680

2 50 24 11,610

3 30 26 12,584

4 28,28 30 14,520

5 31,62 32 15,488

6 80,62 20 9,680Bng 2.13

Cng sut trn ng dy N-1

Cng sut trn ng dy 1-3 Bng 2.14

Phn bcng sut trn mch vng ND-2-6 v i githit bqua tn tht cng sut:


30/74

n Mn Hc Mng Li in


Hnh 2.12

Hnh 2.13

Gis im 6 l im phn cng sut khi ta c:

= 26,417+j12,781MVA

Vy iu gis im phn cng sut l ng.


31/74

n Mn Hc Mng Li in


2.7.2 Chn in p nh mc ca mng in Da vo cng thc kinh nghim Still tnh ton cho tng l ng dy ta c bng

sliu sau:

L N_2 N_6 2_6 N_1 1_3 N_4 N_5

L(km) 50,000 80,620 40,000 40,000 30,000 28,280 58,300Pmax 26,417 17,583 2,417 46,000 26,000 30,000 32,000

Qmax 12,781 8,509 1,171 22,264 12,584 14,520 15,480

Smax 29,346 19,533 2,685 51,102 28,885 33,329 35,547

Ui(kV) 96,312 84,280 39,292 123,405 93,555 99,8746 105,7926Bng 2.14



32/74

n Mn Hc Mng Li in


2.7.3 Xc nh tit din dy dn v cc thng s ca ng dy

L N_2 N_6 2_6 N_1 1_3 N_4 N_5

S mch 1 1 1 2 2 2 2

Pi(MW) 26,417 17,583 2,417 46,000 26,000 30,000 32,000

Qi(MVAr) 12,781 8,509 1,171 22,264 12,584 14,520 15,480

S(MVA) 29,346 19,533 2,685 51,102 28,885 33,329 35,547

Ii(A) 154,209 102,643 11,983 134,226 75,893 87,569 93,397

Fi(mm2) 140,190 93,311 10,894 122,060 68,993 79,608 84,906

DD chn AC-150 AC-95 AC-70 AC-120 AC-70 AC-70 AC-95

Li(km) 50,000 80,620 44,720 40,000 30,000 28,280 58,300

r 0( /km) 0,210 0,330 0,460 0,270 0,460 0,460 0,330

x0( /km) 0,416 0,429 0,440 0,423 0,440 0,440 0,429

b0(106S/km) 2,740 2,650 2,580 2,690 2,580 2,580 2,650

R( ) 10,500 26,604 20,571 10,080 6,900 6,504 9,619

X( ) 20,800 34,585 19,677 16,920 6,600 6,221 12,505

B(10-6S) 137,000 213,643 115,378 215,520 154,800 145,924 308,990

Icp(A) 445,000 330,00 265,000 380,000 265,000 265,000 330,000Kim tra iu kin pht nng dy dn khi sc:

I sc N-1 = I 1 .2 = 134,226.2 = 268,452 A< I cp = 330 A

I sc 1-3 = I 3 .2= 75,893.2 = 151,786 < I cp = 265 A

I sc N-4 = I 4 .2 = 87,569.2 =175,138 A < I cp = 265 A

I sc N-5 = I 5 .2 = 93,397.2 =186,794 A < I cp = 330 A

Xc nh dng in scv i mch kn:

Ngng ng dy ND2:


33/74

n Mn Hc Mng Li in


Ngng ng dy ND6:

Ngng ng dy 26:


2.7.4 Xc nh tn tht in p ln nht ca phng n 2.7.4.1 Ch lm vic bnh thng

L N_2 N_6 2_6 N_1 1_3 N_4 N_5

L(km) 50,000 80,620 40,000 40,000 30,000 28,280 58,300

Ui(kV) 96,312 84,280 39,292 123,405 93,555 99,8746 105,7926

btiU % 4,470 6,298 0,601 6,954 2,169 2,359 4,143Bng 2.12


34/74

n Mn Hc Mng Li in


6,945+2,169=9,114%

=4,470+0,601=5,080%

6,298%

Vy =6,945+2,169=9,114%

2.7.4.2 Ch lm vic sau s c i v i mch lin thng ta ch xt scvi ng dy gn ngun:

6,945+2,169=16,086%

i v i mng in kn ta xt scvi 2 ng dy gn ngun:

t ng dy ND-2:

=

Vy

t ng dy ND-6:

V i

=

Vy

Vy 22,028%>20%

Vy phng n5 khngt yu cu k thut.


35/74

n Mn Hc Mng Li in


CHNG 3 SO SNH KINH T CC PHNG N

3.1PHNG PHP SO SNH KINH T Tiu chun so snh cc phng n vmt kinh t l hm chi ph tnh ton hng

nm b nht. Chi ph tnh ton hng nm ca mi phng n c tnh theo biu thc:

Z = (a tc + a vh ).K + A.c

Z = a tc .K + Y

Trong : Z: Hm chi ph tnh ton hng nm [ng]

tca : Hs nh mc hiu quso snh ca cc vn u t:

tca =tc

1T

tcT : Th i gian tiu chun thu hi vn u t, y ly tcT = 8 nm.Vy tca=0,125.

vha : H s vn hnh hay h s khu hao tu sa th ng k v phc v cc

ng dy ca mng in. Ta ly vha =0,04.K: L vn u t ca mng in. Trong n mn hc ny, vn u t ch

tnh i v i ng dy, cn cc thit b khc nh trm bin p, my ct, dao cch ly..ta coi nh nhau cc phng n:

K = K0i .l i = Ki

iK :Sut vn u t cho 1km ng dy nhnh th I, tit din Fi. V i lkp (2mch) th ly iK =1,6 ln chi ph cho l n c cng tit din dy, (t ng/km).

il :Chiu di truyn ti nhnh thI[km].

imaxA P .

maxP :Tn tht cng sut tc dng ton hthng lc phti cc i (kW).2 2

i iimax i2

dm

P QP .R

U

imaxP : Tn tht cng sut trn ng dy thi lc phti cc i.


36/74

n Mn Hc Mng Li in


: Th i gian tn tht cng sut cc i, ph thuc vo ph ti (th ph ti) vtnh cht ca phti v c tnh bng cng thc:

= (0,124 + T max .10-4 ) 2 .8760 h

maxT : Th i gian sdng cng sut cc i maxT =4800h.

Vy = (0,124 + 4800.10-4)2.8760 = 3195h

c: Gi 1kWh in nng tn tht c=600 ng/kWh.

Gi thnh ng dy trn khng mt mch in p 110kV ( 610 /km).

Ghi ch: Gi thnh ng dy hai mch bng 1,6 ln gi thnh ng dy mtmch.

K hiu dy dn AC-70 AC-95 AC-120 AC-150 AC-185 AC-240

Ct b tng ly tm 300 308 320 336 352 402

Ct thp 380 385 392 403 416 436Bng 3.1

Phng n ti u nht l phng n c hm chi ph tnh ton hng nm Z nhnht.3.2TNH TON V KINH T CHO CC PHNG N

3.2.1 Phng n 1 C bng sliu sau:

L N-1 N-2 1-3 N-4 N-5 N-6

LoiDD AC-120 AC-70 AC-70 AC-70 AC-95 AC-70

Li(km) 40,000 50,000 30,000 28,280 58,300 80,620

K oi(106/km) 320 480 480 480 492,8 480

K i(106) 12800 24000 14400 13574 28730 38697

P(MW) 2,157 0,675 0,475 0.597 1,003 0,756

Bng 3.2


37/74

n Mn Hc Mng Li in


Ta c:

= =19,316.493 kWhVy tc vhZ (a a ).K A.c (0,125+0,04). +19316,493.600

Z =

3.2.2 Phng n 2 C bng sliu sau:

L N_1 N_2 1_3 N_4 4_5 N_6

Loi DD AC-120 AC-70 AC-70 AC-150 AC-95 AC-70

Li(km) 40,000 50,000 30,000 28,280 58,300 80,62

K oi(106/km) 320 480 480 537,6 492,8 480

K i(106) 12800 24000 14400 15203,32 28730,2 38697,6

P(MW) 2,175 0,675 0,475 0,943 1,004 0,756

Bng 3.3Ta c:\

= =19259,46 kWh

Vy tc vhZ (a a ).K A.c (0,125+0,04). +19259,46.600

Z =

3.2.3 Phng n4 C bng sliu sau:


38/74

n Mn Hc Mng Li in


L N_1 N_2 N_3 N_4 N_5 N_6

Loi DD AC-70 AC-70 AC-70 AC-70 AC-95 AC-70

Li(km) 40,000 50,000 70,000 28,280 58,300 80,620K oi(106/km) 480 480 480 480 492,8 480

K i(106) 19200 24000 33600 13574 28730 38679

P(MW) 0,750 0,675 1,110 0,597 0,946 0,756

Bng 3.4

Ta c:

= =15444,63 kWh

Vy tc vhZ (a a ).K A.c (0,125+0,04). +15444,63.600

Z =

3.3LA CHN PHNG N HP L NHT

Tk t qutnh ton kinh t- k thut trn ta c bng sau:

Phng n 1 2 4

U btmax% 9,114 5,061

Uscmax% 16,059 16,059 10,122

Z(106) Bng 3.6

Em tnh li Z ca cc phng n. Ti sao ch so snh kinh t 3 phng n 1, 2, 4.

Da vo bng k t quta la chn phng n c hm chi ph tnh ton Z nhnhtlm phng n thit k .

Vy phng n h p l nht c chn thit k l phng n 4


39/74

n Mn Hc Mng Li in


CHNG 4 CHN MY BIN P V S NI IN

4.1 CHN S LNG V CNG SUT CC MY BIN P TRONGCC TRM H P

Trong cc tr m bin p hp, s l ng v cng sut v chng loi cc my binp phthuc vo cng sut v tnh cht ca phti, vo spht trin ca phti trongtng lai, vo scp in p v s ngun cung c p cho tr m. Ng i ta mong mun

chn s l ng v chng loi my t nht c th. Khi chn my bin p cng cnquan tm n s lm vic song song ca chng. Quyt nh cui cng c da trnc s so snh kinh t- k thut cc phngn c thca tr m.

Trong cc tr m bin p c hai cp in p, ng i ta dng my bin p ba pha haidy qun, c th trong n thit k ta dng my bin p ba pha 2 cun dy110/10kV. Vic dng mt hay hai my bin p ph thuc vo tnh cht ca ph ti ,cng sut tiu thca n v mt s iu kin khc nh sbin thin ca phti, iukin chuyn tr lp t. Trong phm vi thit k n ta dng my bin p ba pha v ivn u t v tn tht in nng nhnht c th.

Tr ng h p ph ti loi I cn t hai my bin p. Trong tr ng h p cng sut phti qu l n khng chn c my bin p, ngi ta cng dng hai hay nhiu my

bin p. Tr ng h p tr m ch c phti loi III c th t mt my bin p nu tronghthng c my bin p d tr lu ng sn sng thay thcho my bin p lm vic b sc.

Cng sut ca cc my bin p phi c chn sao cho m bo cung cp introng tnh tr ng lm vic bnh thng tng ng v i phti cc i khi tt ccc my bin p u lm vic. Khi c mt my bin p bt k ngh do schay sa cha haytrong qu trnh vn hnh kinh tca tr m khi phti cc tiu.

Theo quy nh, trong cc iu kin s c ca hthng in, my bin p c php qu ti 40% ( hsmang ti lc sc qtsck = 1,4) khng qu 5 ngy m v th igian qu ti mi ngy khng qu 6 gi v hsph ti ban u tr c lc qu ti 1sck khng qu 0,93.

H s qu ti qtsck = 1,4 c xem nh mt h s tnh ton, c s dng chn cng sut my bin p theo iu kin qu ti sc. Khi chn cc my bin p, tann tnh ton n kh nng qu ti ca chng c thgim c cng sut t v tnhao trong cc my bin p cng nh t hiu qucao nht v iu kin kinh t- k

thut.Cng sut ca cc my bin p c chn theo cng thc sau:


40/74

n Mn Hc Mng Li in


V i phti loi I: I IIqtsc dm pt maxk .S S

V i phti loi III: dm pt maxS S

Trong : maxs : cng sut yu cu lc phti cc i

qtsck : hsqu ti ssk = 1,4

Trong phm vi n mn hc ny, ta coi cng sut nh mc ca my bin p c hiu chnh theo iu kin kh hu.

4.1.1 Ph ti I Phti I l phti loi I

Vy ta chn 2 my bin p loi TPDH 16000/110.

4.1.2 Ph ti II Phti II l phti loi I


4.1.3 Ph ti III Phti III l phti loi I


4.1.4 Ph ti IV Phti III l phti loi I


4.1.5 Ph ti V Phti III l phti loi I



41/74

n Mn Hc Mng Li in


4.1.6 Ph ti VI Phti III l phti loi I


4.1.7 Thng s cc my bin p

Loi my bin p S liu k thut S liu tnh ton

UcdmkV

UhdmkV

Un% Pk WP0

Kw I0% R X Q0k

VAr

TPDH 16000/110 115 11 10,5 85 21 0,85 4,38 86,7 136

TPDH 25000/110 115 11 10,5 120 29 0,8 2,54 55,9 200

TPDH 32000/110 115 11 10,5 145 35 0,75 1,87 43,5 240Hnh 4.1

4.2CHN S NI DY TRM H P

4.2.1 Trm ngun Do phti gm 6 h tiu thloi I nn m bo cung cp in lin tc ta s

dng s h thng 2 thanh gp lm vic song song. Khi vn hnh h thng mtthanh gp vn hnh cn mt hthng thanh gp dtr .

I DCL

MC

I

Hnh 4.2


42/74

n Mn Hc Mng Li in


4.2.2 Trm trung gian Sdng s hthng thanh gp phn on:

Tngun inn tr m cui

Hnh 4.3

4.2.3 Trm cui Do yu cu vn hnh kinh ttr m bin p khi phti ch cc tiu c thct

ra b t 1 MBA khi tr m nn ta chn s cu i v i tr m cui.Dng h thng c hai phn on thanh gp:

Nu l 70(km) th t my ct cao p pha ng dy b i v v i chiu di l n s cxy ra do thao tc ng ct nhiu v vy phi t my ct cui ng dy.

Vi l


43/74

n Mn Hc Mng Li in


(L70km)

Hnh 4.4

10kV

10k


44/74

n Mn Hc Mng Li in


4.2.4 S ni dy chi tit li in


45/74

n Mn Hc Mng Li in

L Hi Nam- L p htd3k53 Page 45

CHNG 5 TNH TON PHN B CNG SUT TRONG MNG IN

TNH TON CH XC LP CA MNG IN 5.1 TNH TON CHI TIT S PHN B CNG SUT TRONG MNG IN Sau khi tin hnh la chn phng n thit k cho mng in, la chn my bin p

v s ni in cho mng in ta cn phi tin hnh xc nh cc tr ng thi vn hnh inhnh ca mng in. Ch vn hnh ca mng v hthng in c c trng bng ccthng sch ca chng: cc dng cng sut, in p cc nt

Mc ch tnh ch ca mng v h thng in l xc nh cc thng s ch cachng, ngha l tnh cc dng cng sut tc dng v phn khng trong mng in, xc nhin p ti cc nt trong mng in cng nh trn cc thanh gp ca cc tr m tiu th introng cc ch vn hnh bnh th ng khi ph ti cc i v cc tiu, v trong ch saucckhi phti cc i.

Tnh cc ch ca mng v hthng in c thc hin trn cc s thay th(mhnh) ca chng.

Khi xc nh cc dng cng sut v cc tn tht cng sut ta ly in p tt ccc nttrong mng in bng in p nh mc i dmU U 110kV .

5.1.1 Ch ph ti cc i

:5.1.1.2 L ng dy N-1

S nguyn l v thay thca mng in:


46/74

n Mn Hc Mng Li in


Hnh 5.2

+ 9,680j MVA; Z N 1= 18,400+17,600j

Tn tht cng sut trong tr m bin p B1:

= 0,123 + 1,882j MVA

Dng cng sut chy vo cun dy cao p ca MBA1:= (20 + 9,680j) + (0,123 + 1,882j)20,123 + 11,562j MVA

Cng sut in dung u vcui ng dy N-1:2

4c cc mQ Q U B 102 2 2

1102 0,516 10-4 0,624 MVAr

Cng sut sau tng tr Z N 1:

(20,123 + 11,562j) 0,624j 20,123 + 10,938j MVA

Tn tht cng sut trn ng dy N-1:

( ) = 0,803+1,057j MVA

Dng cng sut tr c tng tr Z N 1:

(20,213 + 10,938j) + (0,803 + 1,057j)20,016 + 11,995j

MVACng sut yu cu t i phti 1:


47/74

n Mn Hc Mng Li in


(21,016 + 11,995j) 0,624j 21,016 + 11,371j MVA

Tnh ton tng t cho cc on ng dy khc ta c bng k t qusau:

Nhnh diZ ( ) 4B (10 S)2 0iS (MVA) biZ ( ) iS (MVA)

N-1 18,400+17,600j 0,515 0,042+0,27j 2,19+43,35j 20+9,68j

N-2 11,500+11,000j 1,290 0,058+0,4j 1,27+27,95j 24+11,61j

N-3 16,100+15,400j 1,805 0,058+0,4j 1,27+27,95j 26+12,584j

N-4 6,504+6,221j 0,725 0,058+0,4j 1,27+27,95j 30+14,52j

N-5 9,619+12,505j 1,540 0,07+0,48j 0,935+21,75j 32+15,48j

N-6 18,540+17,736 2,075 0,042+0,27 2,19+43,35j 20+9,68jBng 5.1


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n Mn Hc Mng Li in


Nhnh i maxS(MVA) BAS (MVA) CS (MVA)

jQC/2(MVAr) S'' (MVA) dS (MVA) S' (MVA) NiS (MVA)

N-1 20+9,68j 0,123+1,882j 20,123+11,562j 0,624j 20,123+10,938j 0,083+1,057j 21,016+11,995j 21,016+11,371j

N-2 24+11,61j 0,126+1,97j 24,126+13,58j 1,56j 24,126+12,02j 0,690+0,499j 24,816+12,519j 24,816+10,959j

N-3 26+12,584j 0,138+2,152j 26,138+14,736j 2,18j 26,138+12,556j 1,118+1,07j 27,256+13,626j 27,256+11,446j

N-4 30+14,52j 0,164+2,732j 30,164+7,252j 0,887j 30,164+6,375j 0,650+0,622j 30,814+6,997j 30,814+6,120j

N-5 32+15,48j 0,159+2,553j 32,159+18,033j 1,86j 32,159+16,17j 1,03+1,404j 33,189+17,547j 33,189+15,714j

N-6 20+9,68j 0,123+1,88j 20,123+11,49j 2,5j 20,213+8,99j 0,744+0,712j 20,867+9,702j 20,867+7,202j

Tng 0,833+13,169j 4,345+5,364j 157,958+62,816j

Bng 5.2


49/74

n Mn Hc Mng li in

L Hi Nam- l p htd3k53 Page 49

5.1.1.3 Cn b ng ch nh c cng sut trong h thng T bng s liu ta c tng cng sut yu cu trn thanh gp 110 kV cangun in:

ycS 157,9+62,81j MVA

m bo iu kin cn bng cng sut trong h thng, cc ngun in phi cun cng sut theo yu cu. V vy tng cng sut tc dng do h thng v nh my cncung cp:

Pcc = 157,9 MW

Khi h s cng sut ca cc ngun bng 0,85 th tng cng sut phn khng ca h tv nh my in c th cung cp:

Qcc = Pcc tg =157,9 0,62 = 97,89 MVAr

Nh vy :ccS 157,9+ 97,89j MVA

T kt qu trn nhn thy rng cng sut phn khng do cc ngun cung cp lncng sut phn khng yu cu. V vy khng cn b cng sut phn khng trong ch ti cc i.

5.1.2 Ch ph ti cc tiu Xt ch vn hnh kinh t cc trm h p khi ph ti cc tiu.

Trong ch ph ti cc tiu c th ct bt mt my bin p trong cc trm, song phi tho mn iu kin sau:

0 pt gh m

n

n. PS S S

(n 1). P

i vi trm c 2 my bin p th:

0gh m

n

2 PS S .

P

i vi trm c 1 my bin p th:gh mS S

Kt qu tnh cc gi tr cng sut ph ti v cng sut gii hn:


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n Mn Hc Mng li in


Ph ti P0 (kW) P N (kW) Sm(MVA) S pt(MVA) Sgh(MVA) S MB

1 21 85 16 11,109 11,232 1

2 29 120 25 13,328 17,375 13 29 120 25 14,441 17,375 1

4 29 120 25 16,664 17,375 1

5 35 145 32 17,773 22,234 1

6 21 85 16 11,109 11,232 1Bng 5.3

Cc kt qu tnh ton trn cho thy rng, trong ch ph ti cc tiu tt c ccu vn hnh1 my.

Tnh ton tng t ch max ta c bng kt qu tnh ton sau:

Bng thng scc phn ttrong ch cc tiu

Nhnh diZ ( ) 4B (10 S)

2 0iS (MVA) biZ ( ) iS (MVA)

N-1 18,400+17,600j 0,515 0,021+0,135j 4,38+86,7j 10+4,84j

N-2 11,500+11,000j 1,290 0,029+0,2j 2,54+55,9j 12+5,805j

N-3 16,100+15,400j 1,805 0,029+0,2j 2,54+55,9j 13+6,29j

N-4 6,504+6,221j 0,725 0,029+0,2j 2,54+55,9j 15+7,26j

N-5 9,619+12,505j 1,540 0,035+0,24j 1,87+43,5j 16+7,74j

N-6 18,540+17,736 2,075 0,021+0,135 4,38+86,7j 10+4,84jBng 5.4


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n Mn Hc Mng li in


5.1.2.1 L ng dy N-5

Hnh 5.3

10 + 4,84j MVA; Z N 1= 18,4 + 17,6j Tn tht cng sut trong tr m bin p B1:

= 0,061 + 0,945j MVA

Dng cng sut chy vo cun dy cao p ca MBA1:


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n Mn Hc Mng li in


= (10+4,84j) + (0,061 + 0,945j)10,061 + 5,785j MVA

Cng sut in dung u vcui ng dy N-1:

2 4c cc mQ Q U B 102 2 2

1102 0,515 10-4 0,635 MVAr


(10,061+5,785j) 0,6354j 10,061 + 5,15j MVA


( ) = 0,194+0.185j MVA


(10,061 + 5,15j) + (0,194 + 0,185j)1,255 + 5,335j MVA

Cng sut yu cu t i phti 1:

(10,255+5,335j) 0,635j 10,255 + 4,7j MVA

Tnh ton tng t cho cc on dy khc ta c bng kt qu sau:



N-1 18,400+17,600j 0,515 0,021+0,135j 4,38+86,7j 10+4,84j N-2 11,500+11,000j 1,290 0,029+0,2j 2,54+55,9j 12+5,805j

N-3 16,100+15,400j 1,805 0,029+0,2j 2,54+55,9j 13+6,29j

N-4 6,504+6,221j 0,725 0,029+0,2j 2,54+55,9j 15+7,26j

N-5 9,619+12,505j 1,540 0,035+0,24j 1,87+43,5j 16+7,74j

N-6 18,540+17,736 2,075 0,021+0,135 4,38+86,7j 10+4,84jBng 5.5


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n Mn Hc Mng Li in


Nhnh

i minS(MVA)

BAS(MVA) CS (MVA)


N-1 10+4,84j 0,061+0,945 j10,061+5,78

5j 0,63510,061+5,15

j0.194+0,185

j10,255+5,3

35j 10.255+4,7j

N-2 12+5,805j 0.063+0,946 j12,063+6,79

6j 1,5612,063+5,23

6j0,164+0,175

j12,227+5,3

93j12,277+3,83

3j

N-3 13+6,29j 0,069+1,075 j13,069+7,36

5j 2,113,069+5,26

5j0,264+0,252

j13,333+5,5

17j13,333+3,41

7j

N-4 15+7,26j 0,082+1,376 j15,082+8,63

6j 0,87715,089+7,75

9j0,154+0,148

j15,243+7,9

07j15,243+7,02

j

N-5 16+7,74j 0,079+1,27 16,079+9,01 1,86 16,079+7,15 j0,245+0,320

j16,324+7,4

7j16,324+5,61

j

N-6 10+4,84j 0,061+0,94510,061+5,78

5j2,5 10,061+2,65 0,165+0,158

j

10,226+2,8

80

10,226+0,30

8j

Tng 1,186+1,238 j77,650+24,8

7jBng 5.6


54/74

n Mn Hc Mng Li in


5.1.2.3 Cn b ng ch nh c cng sut trong h thng T bng s liu ta c tng cng sut yu cu trn thanh gp 110 kV ca ngun in:

ycS 77,650+24,87j MVA

m bo iu kin cn bng cng sut trong h thng, cc ngun in phi cun cng sut theo yu cu. V vy tng cng sut tc dng do h thng v nh my cncung cp:

Pcc = 77,650 MW


Qcc = Pcc tg = 77,650 0,62 = 48,143 MVAr

Nh vy :ccS 77,650 + 40,143j MVA

T kt qu trn nhn thy rng cng sut phn khng do cc ngun cung cp lncng sut phn khng yu cu. V vy khng cn b cng sut phn khng trong ch ti cc tiu.

5.1.3 Ch s c Khi xt s c t mt mch l kp ta khng gi thit s c xp chng nn ta ch

trng hp ngng mt mch trn cc ng dy ni t ngun n cc ph ti khi ph i.

Thng s ng dy trong ch sc:



N-1 36,800+35,200j 0,257 0,042+0,27j 2,19+43,35j 20+9,68j

N-2 23,000+22,000j 0,645 0,058+0,4j 1,27+27,95j 24+11,61j N-3 32,200+30,800j 0,902 0,058+0,4j 1,27+27,95j 26+12,584j

N-4 13,008+12,442j 0,362 0,058+0,4j 1,27+27,95j 30+14,52j

N-5 19,238+25,01j 0,77 0,07+0,48j 0,935+21,75j 32+15,48j

N-6 37,08+35,472j 1,037 0,042+0,27 2,19+43,35j 20+9,68jBng 5.7


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n Mn Hc Mng Li in


5.1.3.1 L ng dy N-1

Hnh 5.5

20+9,68j MVA; Z N 1= 36,800+35,200j Tn tht cng sut trong tr m bin p B1:

= 0,123 + 1,882j MVA

Dng cng sut chy vo cun dy cao p ca MBA1:


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n Mn Hc Mng Li in


= (20 + 9,680j) + (0,123 + 1,882j)20,123 + 11,562j MVA

Cng sut in dung u vcui ng dy N-1:

2 4c cc mQ Q U B 102 2 2

1102 0,257 10-4 0,310 MVAr


(20,123 + 11,562j) 0,310j 20,123 + 11,252j MVA


( ) = 1,61+1,546j MVA


(20,213 + 11,252j) + (1,61 + 1,546j)21,733 + 12,798jMVA

Cng sut yu cu t i phti 1:

(21,733 + 12,798j) 0,310j 21,062 + 12,488j MVA

Tnh ton tng t cho cc on dy khc ta c bng kt qu sau:



N-1 36,800+35,200j 0,257 0,042+0,27j 2,19+43,35j 20+9,68j

1-2 23,000+22,000j 0,645 0,058+0,4j 1,27+27,95j 24+11,61j N-3 32,200+30,800j 0,902 0,058+0,4j 1,27+27,95j 26+12,584j

3-4 13,008+12,442j 0,362 0,058+0,4j 1,27+27,95j 30+14,52j

N-5 19,238+25,01j 0,77 0,07+0,48j 0,935+21,75j 32+15,48j

N-6 37,08+35,472j 1,037 0,042+0,27 2,19+43,35j 20+9,68jBng 5.8


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n Mn Hc Mng Li in


Nhnh i maxS(MVA) BAS (MVA) CS (MVA)


N-1 20+9,68j 0,123+1,882j 20,123+11,562j 0,310 20,123+11,252j 1,61+1,546j 21,733+12,798j 21,733+12,488j

N-2 24+11,61j 0,126+1,97j 24,126+13,58j 0,780 24,126+12,8j 1,417+1,356j 25,596+14,156j 25,596+13,376j

N-3 26+12,584j 0,138+2,152j 26,138+14,736j 1,09 26,138+13,646j 2,313+2,213j 28,451+15,859j 28,451+14,769j

N-4 30+14,52j 0,164+2,732j 30,164+17,252j 0,938 30,164+16,814j 1,282+1,226j 31,446+18,04j 31,446+17,602j

N-5 32+15,48j 0.159+2,553j 32,159+18,033j 0,931 32,159+17,102j 2,109+2,742j 34,268+19,844j 34,268+18,913j

N-6 20+9,68j 0,123+1,882j 20,123+11,562 1,25 20,123+10,312j 1,566+1,498j 21,689+11,81j 21,689+10,56j

Tng 0,833+13,171j 10,297+10,581j 163,183+87,708j

Bng 5.9


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n Mn Hc Mng Li in


5.1.3.3 Cn b ng ch nh c cng sut trong h thng T bng s liu ta c tng cng sut yu cu trn thanh gp 110 kV cangun in:

ycS 163,183+87,708jMVA

m bo iu kin cn bng cng sut trong h thng, cc ngun in phi cun cng sut theo yu cu. V vy tng cng sut tc dng do h thng v nh my cncungcp:

Pcc =163,183 MW


Qcc = Pcc tg =163,183 0,62 = 101,173 MVAr

Nh vy :ccS 163,183 + 101,173j MVA

T kt qu trn nhn thy rng cng sut phn khng do cc ngun cung cp lncng sut phn khng yu cu. V vy khng cn b cng sut phn khng trong ch ti sc.

5.2 TNH TON IN P TI CC I M N T CA MNG IN

5.2.1 Ch ph ti cc i

Chn in p trn thanh ci cao p h thng l 121kV (Ucs = 121 kV) ng dy N 1

in p trn thanh gp cao p tr m bin p1:

U1 = Ucs - = 121 = 116,066kV

Cng sut trc tng tr trm bin p1 Z b1:

(20,123 + 11,562j) (0,042 0,27j) 20,081+ 11.292j MVA

in p trn thanh gp hp tr m bin p 5 quy vcao p:

U1q = U1 - = 116,066 = 111,470kV

Tnh in p trn cc ng dy cn li c thc hin tng t.

Kt qu tnh in p trn thanh gp h p ca cc trm quy v in p cao trch ph ti cc i cho trong bng sau:


59/74

n Mn Hc Mng Li in


Gi tr in p trn thanh gp h p quy v cao p trong ch ph ti cc i

TrmBA 1 2 3 4 5 6

Uq(kV) 111,470 114,109 111,910 117,054 113,016 111,824Bng 5.10

5.2.2 Ch ph ti cc tiu Chn in p trn thanh ci cao p h thng l 115 kV (Ucs = 115 kV)

ng dy N-1in p trn thanh gp cao p tr m bin p1:

U1 = Ucs - = 115 = 112,543kV

Cng sut trc tng tr trm bin p1 Z b1:

(10,061 + 5,785j) (0,021 0,135j) 10,04+ 5,65j MVA

in p trn thanh gp hp tr m bin p 1 quy vcao p:U1q = U1 -

= 112,543 = 107,8kV


Kt qu tnh in p trn thanh gp h p ca cc trm quy v in p cao trch ph ti cc tiu cho trong bng sau:

Gi tr in p trn thanh gp h p quy v cao p trong ch ph ti cc tiu:

Trm B 1 2 3 4 5 6

Uq(kV) 107,08 109,737 108,537 109,222 109,176 108,180Bng 5.11


60/74

n Mn Hc Mng Li in


5.2.3 Ch sau s c Chn in p trn thanh ci cao p h thng l 121kV (Ucs = 121 kV). Xt trng hp s

c khi ngng mt mch l kp.

Chn in p trn thanh ci cao p h thng l 121kV (Ucs

= 121 kV)

ng dy N 1in p trn thanh gp cao p tr m bin p 1:

in p trn thanh gp cao p tr m bin p1:

U1 = Ucs -

= 121 = 110,668kV Cng sut trc tng tr trm bin p1 Z b1:

(2,123 + 11,562j) (0,042 0,27j) 20,081+ 11.292j MVA

in p trn thanh gp hp tr m bin p 5 quy vcao p:

U1q = U1 - = 110,668 = 105,848kV


Kt qu tnh in p trn thanh gp h p ca cc trm quy v in p cao trong sau s c cho trong bng sau:

Gi tr in p trn thanh gp h p quy v cao p trong ch s c:

Trm B 1 2 3 4 5 6Uq(kV) 105,848 110,048 105,427 111,367 107,757 106,09

Bng 5.12


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n Mn Hc Mng Li in


CHNG 6 IU CHNH IN P TRONG H THNG IN

in p l mt trong nhng ch tiu cht lng in nng quan trng. Nnh h ngnhiu n ch tiu kinh tv k thut ca cc h tiu th. Cc thit b in ch c th lmvic tt trong nhng tr ng hp in nng c cht l ng cao.

Cht lng in nng c nh gi thng qua cc chtiu v lch in p, daong in p , s khng i xng v khng sin. Trong chtiu v lch in p l ch tiu quan tr ng nht. m bo c lch in p cc h tiu thtrong phm vi cho php ta cn phi tin hnh iu chnh in p theo cc cch sau:

Thay i in p cc my pht trong nh my in. Thay i tsbin trong cc tr m bin p (chn u iu chnh ca cc my bin

p)

Thay i cc dng cng sut phn khng truyn ti trong mng in .Thc tcho thy th i v i nhng mng in l n khng th iu chnh in p bng

cch thay i in p ti nh my in, v thay i cc dng cng sut phn khng trnng dy cng khng th p ng c nhu cu v iu chnh in p v cc l do khcnhau nh: n nh cc h thng, vn hnh phc t p v vn u t cao. Do phng php iu chnh in p ca cc my bin p trong cc tr m bin p c dng r ng ri iu chnh in p.

Yu cu iu chnh in p c phn thnh 2 loi:

6.1 YU CU IU CHNH IN P THNG in p yu cu trn thanh gp hp ca my bin p trong tnh tr ng vn hnh bnh

th ng phi tho mn cc yu cu v lch in p trong cc ch :

- Phti cc i : Ucp max% 2,5%

- Phti cc tiu: Ucp min% 7,5%

- Ch sc : Ucp sc% - 2,5%

Vic iu chnh in p c tin hnh nh sau:


62/74

n Mn Hc Mng Li in


' 'max hdmmin

dcycmax yc min

U UUU .

U U 2

Trong : 'maxU ,

'minU l gi tr quy i vpha cao p ca in p trn thanh gp hp

ca cc tr m i v i ch l n nht v nh nht tng ng ( c ly theo cc s liutnh ton ca in p.

ycmaxU , ycminU l gi tr in p yu cu trn thanh gp hp ca tr m trong ccch phti l n nht v nhnht.

hdmU in p nh mc ca cun dy hp ca cc my bin p.

Sau chn u iu chnh tiu chun ca my bin p, gn nht vi u iu chnh tnhton theo cng thc trn.

xc nh in p ca u iu chnh tiu chun c thsdng cng thc sau:

0 cdmtc cdm

n.E .UU U

100

Trong :

cdmU l in p nh mc ca cun dy in p cao.

N stht u iu chnh chn.

0E mc iu chnh ca mi u (%) 0E =2,5%.

i v i cc my bin p khng c iu chnh in p d i ti, u iu chnh khng thayi trong tt ccc ch vn hnh ca mng in.

Sau khi chn u iu chnh tiu chun, cn tnh c cc gi tr thc ca in p trnthanh gp hp ca mi tr m trong tt ccc ch c trng ca mng in cng nhcc lch nhn c ca in p so vi in p nh mc ca cc thanh gp.

Cc in p thc trn thanh gp hp ca tr m c xc nh theo cng thc tng qutsau:

'i hdm

ittc

U .UU

U

Trong 'iU l gi tr quy i v pha in p cao ca in p trn thanh gp hp catr m bin p, tng ng v i cc ch phti l n nht, nhnht v ch sau sc.

lch in p trn thanh gp hp ca tr m c tnh theo cng thc:


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n Mn Hc Mng Li in


it dmi

dm

U UU % .100%

U

Chn u iu chnh in p theo cch trn thng c p dng i v i cc tr m phn phi c yu cu iu chnh th ng.

Trong ni dung n ta c phti 2 c yu cu iu chnh thng, tr c ht ta xt iuchnh thng i v i tt ccc ph ti v xt n iu kin lch in p cho php xt stha mn ca my bin p khng c iu pd i ti.

Ta c bng tnh ton sau:

Trm bin p 1 2 3 4 5 6

Yu cu C KT KT KT KT KT KT

Uq max(kV) 111,470 114,109 111,910 117,054 113,016 111,824

Uq min(kV) 107,080 109,737 108,537 109,222 109,76 108,180

Uq sc(kV) 105,848 110,048 105,427 111,367 107,757 106,090

Uc max 116,778 119,542 117,239 122,628 118,397 117,148

Uc min 117,788 120,071 119,390 120,144 120,736 118,998

U c 117,283 120,126 118,314 121,386 119,566 118,703

N 1 2 1 3 2 1

Utc 117,875 120,75 117,875 123,625 120,75 117,875

Ut max 10,475 10,539 10,516 10,628 10,438 10,508

Ut min 10,063 10,135 10,199 9,916 10,137 10,166

Ut sc 9,87 10,02 9,83 9,90 9,81 9,90Umax(%) 4,75 5,39 5,16 6,28 4,38 5,08

Umin(%) 0,63 1,35 1,99 -0,84 1,37 1,66

Usc (%) -1,3 0,2 -1,7 -1 -1,9 -1Bng 6.1

Da vo bng ta thy dng my bin p khng c iu p d i ti l khng ph hp i

v i c6 phti.Vy ta chuyn sang phng n sdng my bin p c iu p d i ti.


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n Mn Hc Mng Li in


6.2 YU CU IU CHNH IN P KHC THNG in p yu cu trn thanh gp hp ca my bin p trong tnh tr ng vn hnh bnh

th ng phi tho mn cc yu cu v lch in p:

- Phti cc i : Ucp max

% = 5%

- Phti cc tiu: Ucp min% = 0%

- Ch sc : Ucp sc% = 0 - 5%

Vic iu chnh in p c tin hnh theo cc b c sau:

- Tnh in p trn thanh gp hp ca cc tr m quy vpha cao p trong cc ch .

- Tnh cc gi tr in p yu cu trn thanh gp hp ca cc tr m trong cc ch .

Uyc i = Um + Uicp%. Um - Tnh in p u iu chnh.

Uic = iq h myc i

U .U

U

Trong :Uqi l in p trn thanh gp h p quy i v pha in p cao ca cctr m ch i.

Ta c: Uhm= 1,1.Um = 1,1.10 = 11 kV- Chn u iu chnh gn nht.

in p ca u tiu chun c tnh theo:

Uitc = Ucm+ cmn.e%.U

100

Trong n : Stht tiu chn chn.

e% : Phm vi iu chnh gia 2 u iu chnh lin ti p.

Ucm: in p nh mc cao (115 kV).

- Tnh cc gi tr thc ca in p trn thanh gp hp :

Ut = iq hm

tc

U U

U

- Kim tra lch in p thc :

Ui% = t mm

U U

U100%.


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n Mn Hc Mng Li in


Cc tr m u dng cc MBA c phm vi iu chnh in p l 9 1,78% c Ucm = 115kV; Uhm= 11 kV.

Cc u iu chnh in p tiu chun ca MB c iu p di ti:

n 0 1 2 3 4 5 6 7 8 9

Utc 115 117,05 119,10 121,15 123,20 125,25 127,30 129,35 131,40 133,42

n 0 -1 -2 -3 -4 -5 -6 -7 -8 -9

Utc 115 112,95 110,90 108,85 106,80 104,75 102,75 100,65 98,60 96,55Bng 6.2

lch in p trn thanh ci ca tr m phi tho mn iu kin :

- Ch phti cc i:

Uyc max= Um + Ucp max%. Um = 10 + 5%.10 = 10,5 kV

- Ch phti cc tiu:

Uyc min= Um + Ucp min%. Um = 10 + 0%.10 = 10 kV

- Ch sc:

Uyc sc= Um + Ucp sc%. Um = 10 + 5%.10 = 10,5 kV

Ph ti 1

Ta c in p cc u phn p:

+ Ch phti cc i:

in p tnh ton ca u iu chnh ca my bin p c xc nh theo cng thc:

=116,778 kV

Chn u iu chnh tiu chun n = 1 Utcmax= 117,05 kV.

in p thc trn thanh gp hp bng:

=10,475kV

lch in p trn thanh gp hp bng:

4,75%

+ Ch phti cc tiu:

in p tnh ton ca u iu chnh ca my bin p bng:


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n Mn Hc Mng Li in


=117,283kV

Chn n =2 Utcmin= 119,1kV.

in p thc trn thanh gp hp c gi tr :

10,063 kV

lch in p bng:

0,63%

+ Ch sau sc:

in p tnh ton ca u iu chnh ca my bin p bng:

110,888 kV

Chn n = -2 Utcmin= 110,9kV.

in p thc trn thanh gp hp c gi tr :

=9,87 kV

lch in p bng:

=-1,3%Vy cc u chn tho mn yu cu iu chnh in p khc th ng.

Tinh toan tuong tu cho cac TBA2,TBA3, TBA4, TBA5, TBA6. Ket

qua tinh toan duoc cho o bang sau:


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n Mn Hc Mng Li in


B ng 5.2 Thng s cc trm bin p khi s dng MB c i u p di ti

Ch max

Trm bin p 1 2 3 4 5 6

Uqmax(kV) 111,470 114,109 111,910 117,054 113,016 111,824

Ucmax 116,778 119,542 117,239 122,628 118,397 117,148

n 1 2 1 3 1 1

Utcmax 117,05 119,10 117,05 121,15 117,05 117,05

Utmax 10,475 10,539 10,516 10,628 10,438 10,508

Umax(%) 4,75 5,39 5,16 6,28 4,38 5,08


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n Mn Hc Mng Li in


Ch min

Trm bin p 1 2 3 4 5 6

Uqmin(kV) 107,080 109,737 108,537 109,222 109,76 108,180

Ucmin 117,788 120,071 119,390 120,144 120,736 118,998

N 1 2 2 3 3 2

Utcmin 117,05 119,1 119,1 121,15 121,15 119,1

Utmin 10,063 10,135 10,199 9,916 10,137 10,166

Umin(%) 0,63 1,35 1,99 -0,84 1,37 1,66


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n Mn Hc Mng Li in


Ch s c

Trm bin p 1 2 3 4 5 6

Uqsc(kV) 105,848 110,048 105,427 111,367 107,757 106,090

Ucmax 110,888 115,288 110,447 116,670 112,888 111,141

n -2 0 -2 1 -1 -1

Utcmax 110,9 115 110,9 117,05 112,95 112,95

Utmax 10,49 10,52 10,45 10,46 10,49 10,33

Umax(%) 4,9 5,2 4,5 4,6 4,9 3,3


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n Mn Hc Mng Li in


CHNG 7 CC CH TIU KINH T K THUT CA MNG IN

7.1 VN U T XY DNG MNG IN

Tng cc vn u t xy dng mng in c xc nh theo cng thc:

K = tK K

Trong K : tng vn u t xy dng cc ng dy.

K t: vn u t xy dng cc tr m bin p.

Ta tnh c tng vn u t xy dng cc ng dy: K = 157783 106

Trong hthng in thit k c 6 tr m hp, 6 tr m c 2 my bin p do vn u tcho cc tr m hp:

K t = 1,8.(3 22.109 + 2 13.109) +29=217,8.109

Do tn vn u t xy dng mng in:

K = K + K t = 157783 106 + 217,8 109 = 375583 106 ng

7.2 TN THT CNG SUT TC DNG TRONG MNG IN Tn tht cng sut tc dng trong mng in gm c tn tht cng sut trn ng dyv

tn tht cng sut tc dng trong cc tr m bin p ch phti cc i. - Tng tn tht cng sut tc dng trn cc ng dy:

Pd=PdN-1+P N-2+PdN-3+Pd N-4+PdN-5+PdN-6 = 4,834MW

- Tng tn tht cng sut tc dng ca cc trm bin p:

PBAi = PBA1+PBA2+PBA3+PBA4+PBA5+PBA6= 0,43 MW

Nh vy tng tn tht cng sut tc dng trong mng in:

P = Pd + PBAi= 4,834+ 0,43 = 5,26 MWTn tht cng sut tc dng trong mng in tnh theo phn trm (%):

3,46%7.3 TN THT IN NNG TRONG MNG IN Tng tn tht in nng trong cc trm bin p xc nh theo cng thc sau:

2

maxi

BAi 0i Nim

S1A n P t P

n S


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n Mn Hc Mng Li in


Y = 0,04 157783 106 + 0,1 217,8 109 + 19942,063 103 600

= 40,056 109 ng

7.4.2 Chi ph t nh ton hng nm

Chi ph tnh ton hng nm c xc nh theo cng thc: Z = atc K + Y

Trong

atc: hs nh mc hiu quca cc vn u t (atc = 0,125).

Do chi ph tnh ton bng:

Z = 0,125 375583 106 + 40,056 109 = 87,003 109

7.4.3 Gi thnh truy n ti in nng Gi thnh truyn ti in nng c xc nh theo cng thc:

54,901/kWh

7.4.4 Gi thnh y dng 1 MW cng sut ph ti trong ch cc i Gi thnh xy dng 1 MW cng sut phti c xc nh theo biu thc:

2,470.109 /MW

K t qucc ch tiu kinh t - k thut ca h thng in thit k c tng hp d i bng sau:

Cc ch tiu kinh t- k thut ca hthng in thit k :


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n Mn Hc Mng Li in


Cc ch tiu n v Gi tr

1. Tng cng sut ph ti khi cc i MW 152

2. Tng chiu di ng dy km 327,23. Tng cng sut cc MB h p MVA 278

4. Tng vn u t cho mng in 109 375,583

5. Tng vn u t v ng dy 109 157,783

6. Tng vn u t v cc trm bin p 109 217,80

7. Tng in nng cc ph ti tiu th MWh 729600

8. Umaxbt % 5,061

9. Umaxsc % 10,12

10. Tng tn tht tht cng sut P MW 5,26

11. Tng tn tht cng sut P % 3,46

12. Tng tn tht in nng MWh 19942,063

13. Tng tn tht in nng % 2,733

14. Chi ph tnh ton 109 87,033

15. Chi ph vn hnh hng nm 109 40,056

16. Gi thnh truyn ti in nng /kWh 54,901

17. Gi thnh xy dng 1 MW cng sut ph ti khi cc i109 /MW 2,470Bng 7.1


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n Mn Hc Mng Li in

TI LIU THAM KHO

[1].Nguyn Vn m. Thi t k cc m ng v h thng in. Nh xut bn khoahc k thut, 2004.

[2]. Trn Bch. Li in v h th ng in t p 1, 2, 3 . Nh xut bn khoa hck thut, 2004.

[3]. Trn Bch. n nh trong h thng in. i hc Bch Khoa H Ni,2001.

[4]. Trn Bch. T i u ha cc ch ca h thng in. Trng i hcBch Khoa H Ni, 1999.

[5]. o Quang Thch, Phm Vn Ha. Phn in trong nh my in vtr m bi n p . Nh xut bn khoa hc k thut, 2005.

[6]. Nguyn Ln Trng. Quy ho ch v pht tri n hthng in. Nh xut bnkhoa hc k thut, 2004.

[7]. L Vn t. Ng n mch trong h thng in. Nh xut bn khoa hc k thut, H Ni 2005.

[8]. Trn nh Long. T ng ha trong h thng in. Trng i hc BchKhoa H Ni, 2005.