March 28, 2015
1
Ho Chi Minh City University of Technology
PGS.TS L Minh Phng
Khoa in in TTrng i Hc Bch KhoaTP H CH MINH
Contact info:Address: 268 L Thng Kit, P.14,Q.10, TP H Ch MinhTelephone: 84-08-38647256 (5722)Mobile: 0988572177E-mail: [email protected]; [email protected],
March 28, 2015
Energy saving
TIT KIM IN NNGTRONG CNG NGHIP V DN DNG
PGS.TS L Minh PhngKhoa in in T
Trng HBK TPHCM
TPHCM2014Saturday,
March 28, 2015
PGS.TS Le Minh Phuong
Energy saving
Chng 2 Tn hao k thut v phng php tnh
Tn tht c ti
Tn tht cng sut tc dng khi c ti P trong liin 3 pha vi in tr ca pha l R v dng in l I c xc nh theo cng thc:
Cng sut biu kin S vi in p pha Up v in pdy U
23P I R
3 3UIpS U I I=
3SU
;
Saturday, March 28,
2015 PGS.TS Le Minh Phuong
Energy saving
Khi tn tht cng sut tc dng c tnh
Trong PP v PQ tn tht cng sut do cng sut tc
dng v cng sut phn khng gy ra. in p U l in p ti nt vi cng sut P v Q
(Nu cho trc P v Q ti im u th in p U cng ti im u v ngc li).
2 2 2 22
2 2
(1 )3 P QP Q P tgP I R R P P R
U U
Thng tin v P,Q,U
Saturday, March 28,
2015
March 28, 2015
2
PGS.TS Le Minh Phuong
Energy saving
Tuy nhin Gi tr P v Q trong cc nhnh thng khng cho
trc m ch bit ti ti cc nt. V vy trc ht phi gii quyt bi ton tnh ton
phn b cng sut trong ch xc lp l xc nhP v Q trong tng nhnh t nhng d liu chotrc.
Saturday, March 28,
2015 PGS.TS Le Minh Phuong
Energy saving
Nhn xt Tn tht in nng l tng tn tht cng sut ca
tt c cc ch trong thi gian tnh ton.
tnh ton tt c cc gi (720-744 gi/thng hoc8760 gi/nm) cn phi bit ti ti cc nt tt ccc gi .
thc hin vic ny phi c thit b o lngcng sut, in p t xa v t ng truyn d liuv trung tm tnh ton trong ch online.
Saturday, March 28,
2015
PGS.TS Le Minh Phuong
Energy saving
Nu thc hin vic o lng ti tt c cc nhnhth khng cn phi tnh ton phn b cng sut mch cn tnh tng tn tht cng sut ca tng nhnhtheo cng thc trn.
Thc t cho thy thit b o lng t xa mi chc lp t cho li 110kV tr ln. Trong khi li22kV v 0,4 kV khng y cho tt c cc nhnh.
V vy, nhim v xc nh tn tht in nng trongthng, nm trn c s tnh ton tn tht cng sutcho li 6-22kV v 0,4 kV.
Saturday, March 28,
2015 PGS.TS Le Minh Phuong
Energy saving
Xc nh tn tht trong li 110kV tr ln i vi li 110kV v cao hn c lp t cc
thit b o lng t xa, nn P v Q ti cc nt cbit trc v v vy c th xc nh tn tht trongcc phn t.
Vic tnh ton tn tht t bi ton phn b cngsut l khng cn thit i vi li 110kV tr ln.
Saturday, March 28,
2015
March 28, 2015
3
PGS.TS Le Minh Phuong
Energy saving
Xc nh tn tht trong li 6-22kV Trong li 6-10-22kV thng thng ta ch bit
c in nng tiu th ti cc trm tng, qua xc nh c cng sut P,Q trung bnh ti ccng dy u.
xc nh P, Q trong tng phn t phi chpnhn gi nh vic phn b cng sut gia ccnhnh: ti t l thun vi cng sut lp t, sau bng php tnh lp i lp li t trn xung, t diln cho n khi cn bng tng ti cc nhnh vtn hao bng ti ti nt .
C th xc nh t l ti bng cch o th ccnhnhSaturday, March 28,
2015 PGS.TS Le Minh Phuong
Energy saving
Xc nh tn tht trong li 0,4 kV i vi li h th 0,4kV khi bit s v thng s
cc phn t, vic tnh ton tng t nh li 6-22kV.
Tuy nhin, s ng dy 0,4 kV rt nhiu v khngcn bng gia cc pha nn vic thc hin tnh tons rt kh khn v thng phi tnh ton gn ng.
Saturday, March 28,
2015
PGS.TS Le Minh Phuong
Energy saving
Kt lun
Nh vy c th ni tn ti 3 phng php tnh tontn tht in nng:
Phng php trc tuyn: theo d liu truyn v tthit b o lng t xa
Phng php phn tch: s dng gii thut tnhton phn b cng sut, cho php phn tch nhhng ca s thay i s , ti hay ch ntn hao.
Phng php nh gi: da trn c s d liuchung ca li
Saturday, March 28,
2015 PGS.TS Le Minh Phuong
Energy saving
Cc phng php tnh tn tht khi c ti
Saturday, March 28,
2015
March 28, 2015
4
PGS.TS Le Minh Phuong
Energy saving
c tnh th ph tiKhi tnh ton tn tht in nng theo tn hao cngsut s dng i lng ph ti cc i hoc ph titrung bnh. V hai i lng Tmax thi gian ti cci, - thi gian tn hao cc i
Saturday, March 28,
2015
Energy saving
in nng tiu th
Tmax: thi gian cng sut cc i, trong khongthi gian ph ti cc i Pmax tiu th lngin nng ng bng lng in nng ph ti thct tiu th trong khong thi gian kho st T
1
n
P i ii
A P t
max maxPA P T
PGS.TS Le Minh Phuong
Saturday, March 28,
2015
Energy saving
Tn hao in nng
: thi gian tn hao cng sut cc i, trongkhong thi gian dng cc i Imax gy ra tnhao in nng ng bng lng tiu hao do dngthc t gy ra trong khong thi gian kho st T
2
13
n
P i ii
A R I t
2ax3P mA RI
PGS.TS Le Minh Phuong
Saturday, March 28,
2015 PGS.TS Le Minh Phuong
Energy saving
c tnh th ph tiHai i lng c tnh trong n v tng i :
Trong : Pi cng sut bc th I ca th ph tiPmax cng sut cc iPtb cng sut trung bnhT thi gian kho st
2
2max
i iP tP T
1max
max max
n
i ii P
PtAT
P T P T
Saturday, March 28,
2015
March 28, 2015
5
PGS.TS Le Minh Phuong
Energy saving
i lng h s hnh dng khd
Quan h gia hai i lng trn:
Trong kdk h s in kn th v c tnh bng t s thigian ti cc i v thi gian kho st
22
21
Ti i
hdi tb
P tkP T
2 2dk hdk k
axmdk
TkT
Saturday, March 28,
2015 PGS.TS Le Minh Phuong
Energy saving
Mt s nghin cu trnh by cng thc tnh thi giantn hao cc i v h s hnh dng khd
223
dk dkk k 21 2
3dk
hddk
kkk
2
2 2(3 2)hd
hd
kk
Saturday, March 28,
2015
PGS.TS Le Minh Phuong
Energy saving
Tn tht in nng tnh theo hai phng php
Theo tn tht cc i
Theo tn tht trung bnh
axW mP T
2W tb hdP Tk
Saturday, March 28,
2015 PGS.TS Le Minh Phuong
Energy saving
Bi tpXc nh tn tht in nng tc dng v phn khngtrn dy dn li 10kV 3x150mm2 chiu di 2 kmtrong 1 nm nu bit cng sut cc i l S=3+j1,3(MVA) v Tmax=2900h.
Saturday, March 28,
2015
March 28, 2015
6
V DXc nh tn hao in nng trong 01 nmtrn dy dn AC in p 6 kV, chiu di dydn l 8.2 km, tit din dy dn l 95mm2(R0=0.33 /km). in nng tiu th trong mtnm l 4980 MWh, vi ti cc i I2max=100A v cos=0.8. Khd=1.05 (gii bng 2 cch)
Saturday, March 28,
2015 PGS.TS Le Minh Phuong PGS.TS Le Minh Phuong
Energy saving
TN THT TRONG CC PHN T
Saturday, March 28,
2015
Tn hao cng sut trong MBA
S thay th ca MBA
23PGS.TS Le Minh Phuong
Energy saving
2_
2_
MBAM
MBAMNMMBA S
UPR
MBAM
MBAMNMMBA S
UUZ_
2_
100
Tn hao cng sut tc dng : bao gm tnhao do pht nng cun dy, ph thuc vodng in ti v tn hao trong li thpkhng ph thuc vo ti P0
02
22
2
22
PRU
QPPRU
QPP MBAMBA
FeMBAMBA
MBA
PGS.TS Le Minh Phuong
Energy saving
Saturday, March 28,
2015
March 28, 2015
7
T thng s nh mc ca MBA v bin i biuthc trn ta c
02
_02
_
)( PKPPS
SPP MBAPTNMMBAM
NMMBA
Trong P0(%)- Tn hao cng sut khng ti ca MBA.PNM(%) Tn hao cng sut ngn mch MBA.Kpt h s mang ti MBA (Kpt=S/Smba)
PGS.TS Le Minh Phuong
Energy saving
Saturday, March 28,
2015
Tn hao cng sut phn khng : bao gmtn hao do phn tn t thng MBA , phthuc vo bnh phng dng in ti v tnhao t c xc nh bi dng in khngti Q0
02
22
QXU
QPQQQ MBAMBA
MBA
MBAMSIQQ _00 100
%
26PGS.TS Le Minh Phuong
Energy saving
Saturday, March 28,
2015
Tng tn hao cng sut phn khng
Trong Trong I0(%)- Dng in khng ti ca MBA.UNM(%) - in p ngn mch MBA.
2_2 2 0
0 __
_ 2_ 0
%3 3100 100
( %)100
M MBANMMBA MBA M MBA
M MBA
M MBAMBA NM PT MBA
UU IQ I X Q I SS
SQ U K I
PGS.TS Le Minh Phuong
Energy saving
Saturday, March 28,
2015
Tn hao in nng trong MBATn hao in nng tc dng
Tn hao in nng phn khng
2
2ax_ 0 _ _max 0
_
mP MBA NM NM PT MBA
M MBA
SA P PT P K PTS
_ 2_ 0 _ _max 0( )100
M MBAQ MBA NM PT MBA
SA Q Q T U K I T
Trong Smax l cng sut cc iT thi gian kho stPGS.TS Le Minh Phuong
Energy saving
Saturday, March 28,
2015
March 28, 2015
8
Tn hao cng sut trong n-MBA l vicsong song
Tn hao cng sut tc dng
Tn hao cng sut phn khng
2
2ax0 _ _ max 0
_
_ mNM NM PT MBAM MBA
SP MBA n P n P n P K n PnS
2
_ ax0
_
_ ( )100M MBA m
NMM MBA
S SQ MBA n Q n Q T nU nInS
PGS.TS Le Minh Phuong
Energy saving
Saturday, March 28,
2015
Tn hao in nng trong n-MBA l vicsong song
Tn hao in nng tc dng
Tn hao in nng phn khng
2
2ax_ 0 _ _max 0
_
mP MBA NM NM PT MBA
M MBA
SA n P n PT n P K n PTnS
_ 2_ _ _ max 0
1( )100M MBA
Q MBA NM PT MBA
SA n Q n Q T U K nI T
n
PGS.TS Le Minh Phuong
Energy saving
Saturday, March 28,
2015
PGS.TS Le Minh Phuong
Energy saving
Tnh ton tn tht trong li 6-22kVLi 6-22 kV c c tnh l s n gin c nhiung dy tuy nhin t thng tin v ti ca cc trmbin p 6-22/0.4kV. V vy ta s dng phng phpm hnh ha li in dng in tr tng ng.
Saturday, March 28,
2015 PGS.TS Le Minh Phuong
Energy saving
Tnh ton tn tht trong li 6-22kV
Saturday, March 28,
2015
March 28, 2015
9
PGS.TS Le Minh Phuong
Energy saving
Tnh ton tn tht trong li 6-22kVTn tht c ti trong ng dy c th c xcnh theo
2 2 2 21 _ 1 _
21
W WW P hd P Q hd QL LP td
k kR
TU
2 2 2 2
1 12
1
(W W )W P Q hdL LP td
kR
TU
Trong WP1, WQ1 in nng tc dng v phn khng iqua nt u tin ca li.U1 in p dy nt u tin khi ti ln nhtkhd_P, khd_Q h s hnh dng th ph ti P v Qkhd h s hnh dng th ph ti PRtd in tr tng ng ca liT thi gian kho st
Saturday, March 28,
2015 PGS.TS Le Minh Phuong
Energy saving
- h s tnh n s khc bit gia th ph ti P v Q.
Nu khng c thng s v gc th c th chn =1,0-1,05;Rtd in tr tng ng ca liU1 in p ti nt u tin khi ti l ln nht
2ax min( )1
24m
max , min Gc lch ln nht v nh nhttrong li in (rad)
Saturday, March 28,
2015
PGS.TS Le Minh Phuong
Energy saving
in tr, dn tng ng ca li 6-22 kV cth c xc nh khi khng c thng tin v ti trongcc nhnh vi gi thit ti t l vi cng sut nhmc ca MBA
2 2, , , ,
1 12
n m
L i T i T j T ji j L T
td td tdT
R S R SR R R
S
2 2, , , ,
1 12
n m
L i T i T j T ji j L T
td td tdT
X S X SX X X
S
0,1
2
m
jjT
tddm
PG
U
0, ,
12
n
j T jjT
tddm
I SB
U
Trong ST,i cng sut nh mc ca my bin p, nhn nnglng theo ng dy th i vi in tr RL,iST,j cng sut nh mc ca my bin p, vi in trRT,jn- s ng dym- s my bin pST tng cng sut nh mc ca MBA G- in dnB Dung dn
Saturday, March 28,
2015 PGS.TS Le Minh Phuong
Energy saving
1. Tn tht in nng phn khng trn ng dytrn khng (Tn tht trong cable c th b qua)
2. Tn tht in nng tc dng khng ti ca mybin p c xc nh t thng s nh mc camy bin p WP0
3. Tn tht in nng phn khng khng ti ca MBA
W WL
L LtdQ PL
td
XR
0W WT
T TtdQ PT
td
BG
W % /100TQ DMMBAS I
Saturday, March 28,
2015
March 28, 2015
10
PGS.TS Le Minh Phuong
Energy saving
4. Tn tht c ti trong MBA phn phi c th cxc nh theo
Trong WPT, WQT in nng tc dng v phn khngc truyn ti qua MBA
5. in nng pha in p cao
2 2 2 2_ _
2,1
W WW
T TP hd P Q hd QT T
P tdT
k kR
TU
2 2 2 2
2,1
(W W )W
T TP Q hdT T
P tdT
kR
TU
1 0 ,W W W W WT L TP P P P P CAO
1 0 ,W W W W WT L TQ Q Q Q Q CAO
Trong :Wp0(T) , Wq0(T) tng tn tht khng ti trong MBA
Saturday, March 28,
2015 PGS.TS Le Minh Phuong
Energy saving
Nu khng c thng tin v ng dy cho cc tipha cao p khi
WP,CAO, WQ,CAO in nng tc dng v phn khngca ti c cung cp pha in p cao
UT,1 in p tnh ton quy v pha in p thp
, 1W WCAOP CAO PPP
, 1W WCAOQ CAO QQQ
1 1,1 1
1
W WU
L Ltd P td Q
T
R XU
TU
Saturday, March 28,
2015
PGS.TS Le Minh Phuong
Energy saving
Bi tpXc nh in tr tng ng v tn tht ca li 10kV nubit in nng tiu th l 2300MWh/nm v 17000MVarh/nm. in tr MBA 100kVA,160kVA,250kVA ln lt l 24; 10,4;5,9, h s in kn th l 0.35 ; =1.03; cos=0.9;
Saturday, March 28,
2015 PGS.TS Le Minh Phuong
Energy saving
Bi tp
MBA110/10kV
U (%) DPNM(KW)
DPo(KW)
Io(%) R X DQ0
100 5 2.1 0.32 2.6
160 5 2.8 0.5 2.4
250 5 4 1.05 2.9
320 5 5.3 1.6 5.6
400 5 6.25 2 4
Saturday, March 28,
2015
March 28, 2015
11
PGS.TS Le Minh Phuong
Energy saving
Xc nh in tr tng ng v tn tht ca li10kV nu bit in nng tiu th l 1140MWh/qu v700Mvarh/qu. in p ti on 0-1 trong thi imti ln nht l 10,4kV v in p trung bnh l 10,5kV. H s hnh dng l Khd^2=1,1. ac 35 0.85+j0.56Ac 25 1.38+j0.687
Saturday, March 28,
2015 PGS.TS Le Minh Phuong
Energy saving
Thng s nh mc ca MBA theo bng.
S(kVA) U(%) Pnm(kW) I0(%)400 5 2,0 6,25 4,0
320 5 1,6 5,3 5,6100 5 0,3 2,34 2,4
Saturday, March 28,
2015
PGS.TS Le Minh Phuong
Energy saving
Phng php tnh ton tn tht trong li 0,4kVLi 0,4 kV thng thng l s hnh tia kt nithng qua thanh ci sau my bin p phn phi 6-22kV/0,4kV.
Li 0,4 kV trong thnh ph s dng cable cnnng thn th vn cn s dng dy trn.
Nu ta bit s , thng s ca ng dy h th, ti trong cc nt th vic tnh ton tn tht l khngkh khn v c th tin hnh thc hin nh li 6-22kV.
Saturday, March 28,
2015 PGS.TS Le Minh Phuong
Energy saving
Phng php tnh ton tn tht trong li 0,4kVKhi khng c thng tin v ti ca cc khu nh v chbit in nng cung cp qua my bin p phn phiti on dy u tin.
Li in sinh hot 0,4 kV khng c lp t y ng h in v vic nhp d liu v in nngtiu th cng khng th nhanh v c, c bit cc vng nng thn.
V vy, xc nh tn tht trong li 0,4kV thngphi p dng bin php tnh ton da trn ccphng php gn ng.
Saturday, March 28,
2015
March 28, 2015
12
PGS.TS Le Minh Phuong
Energy saving
1. Phng php tnh ton trn c s d liu tngqut v tng chiu di ng dy: phng phpny da vo thng tin v chiu di dy dn, sloi tit din v in nng truyn ti trn ccng dy ny.
2. Phng php tnh ton da vo tn hao in p. Phng php ny s dng mi quan h gia gitr tng i tn tht in p v tn tht cng suttrong cc phn t li in. Cn phi o in ptrn thanh ci my bin p phn phi v in pti im xa nht trong li.
Saturday, March 28,
2015 PGS.TS Le Minh Phuong
Energy saving
Nhn xtTng chiu di ng dy hay tn tht in pkhng th m t y v chnh xc tn tht innng, v chng ph thuc rt nhiu vo phn b phti cng nh cu trc ca s .
V vy cn thit phi m t s li mt i lngtng qut d xc nh sau tm mi quan h ca ilng ny vi tn tht cng sut. Di y trnh bymt s yu t, i lng nh hng ti tn tht.
Saturday, March 28,
2015
PGS.TS Le Minh Phuong
Energy saving
Phng php tnh ton trn c s d liu tngqut v tng chiu di ng dy:
1. nh hngca phn b ph ti trn ngdy
Phn b ph ti trn ng dy cung cp in chosinh hot c th coi l phn b u, c bit l ccvng nng thn, dy dn thng lp t dctheo ng v c theo mt khong chiu di nhnhau c ni ti gn tng t nhau.
Cc nh my cng nghip thng nm xa khu dnc v c ng dy ring bit ng dy ti tptrungSaturday,
March 28, 2015 PGS.TS Le Minh Phuong
Energy saving
Tn tht c ti trong cc ng dy c xc nh
in tr tng ng ph thuc vo cu trc ngdy v phn b ph ti
2 2 2
2
W (1 )W hd tdtg k R
TU
Trong W in nng truyn ti trn ng dy trong thi gian T (gi)tg - h s cng sut phn khngkhd- h s hnh dng th ph tiU- in p liRtd in tr tng ng ca li.
Saturday, March 28,
2015
March 28, 2015
13
PGS.TS Le Minh Phuong
Energy saving
Xc nh in tr tng ng1. i vi ng dy cng tit din v ti tptrung cui ng dy (Gi thit cos=1)
0tdR r L
22
1 023 tdPP I R r LU
Trong R0 in tr xut ca dy dn (/km)L - chiu di ca dy dn (km)
Saturday, March 28,
2015 PGS.TS Le Minh Phuong
Energy saving
2. i vi ng dy cng tit din v ti phn bu trn ng dy
Tn tht trn ng dy ti phn b u =1/3 tn thttrn ng dy ti tp trung cui ng dy
Saturday, March 28,
2015
13deu taptrung
P P
PGS.TS Le Minh Phuong
Energy saving
Phn tch: Gi thit ph ti phn b u t An B vi mt cng sut p0(W/m)
Tng cng sut trn ng dy= cng sut onu
0 0 00 0
L LP p dl p l p L
Saturday, March 28,
2015 PGS.TS Le Minh Phuong
Energy saving
Cng sut trn on dl
Gi thit cos=1 dng in v tn tht trn on dl
Tng tn tht trn c on AB
00 0 0
( ). ( )L
dll
L p L l L L lp p dl p l p L l Pl L L
0 ( )3 3
dldl
p p L lI
U U
2
2 00 0
( )3 33dl dl
p L lP I r dl r dlU
2 2 2 320 0 0 0 0
0 2 20 0
( ) ( )3 ( )
033
L L Lp L l p r p r L lP r dl L l dlU UU
2 2 22 20 0 0
0 1 12 2 3 33 3 3 tdp L r L r LPP r L I I R
U U 0
3tdr LR
Saturday, March 28,
2015
March 28, 2015
14
PGS.TS Le Minh Phuong
Energy saving
Cch phn tch khcCn bng cng sut
Thay hai biu thc ta c
Nh vy, vi cng chiu di v tit din ph ti phnb u, in tr tng ng hay tn tht ca linh hn 3 ln so vi trng hp ti tp trung cuing dy
2 20
0
( )L
tdP R p l r dl
( ) L lp l PL
22 2
00
L
tdL lP R P r dl
L
3
00
103 3tdL r LL lR r
L
Trong P cng sut ti on u ca nhnhp(l) cng sut ti on dl
Saturday, March 28,
2015 PGS.TS Le Minh Phuong
Energy saving
Cng thc tng qut vi n ti phn b trn ng dy
Gi tr kL thay i t 1 n 1/3. Tuy nhin thc tcho thy phn b ph ti khng tuyt i u.
Bng thc nghim phn tch 144 s cho thykL=0.37 l nh nht
Trong dp l t l ph ti sinh hotng dy tp trung dp=0ng dy phn b dc ng dy dp=1
0 02
( 1)(2 1)6td L
n nR r L k r Ln
1 0,63L pk d
Saturday, March 28,
2015
Khi s phc tp, c th tnh gn ng
Nu L_I ln hn nhiu th
Energy saving
2,
2,
(1 )i pt idt Ipt i I
R KR R
K R
2
,2
,
(1 )i pt idt Ipt i I
X KX X
K X
,
ax,
ipt i
m i
PKP
2(1 )i
dt II
RR R
n R 2(1 )idt I
I
XX X
n X
Saturday, March 28,
2015 PGS.TS Le Minh Phuong
Energy saving
Phng php tnh tn tht theo tng chiu di ngdy
Nu l dy nhm (=28,2.10-8m)
Nu l dy ng (=17,2.10-8m)
Vi 0.37kL1
2 2 2
2
W (1 ) 28, 2W hd Ltg k k L
TU F
2 2 2
2
W (1 ) 17, 2W hd Ltg k k L
TU F
Saturday, March 28,
2015
March 28, 2015
15
PGS.TS Le Minh Phuong
Energy saving
Bi tpXc nh tn tht cng sut trn 1 km ng dy A-90(r0=0.34/km; x0=0.4 /km), nu bit nng lngtiu th l 10MWh trong 1 thng (30 ngy), in p l380V. Cc thng s cn li tg=0.5; kdk=0.3;kunbalance=1.05; kN=1. Ti tp trung cui ngdy
Saturday, March 28,
2015 PGS.TS Le Minh Phuong
Energy saving
Cc yu t nh hng n tn tht1. nh hng ca phn nhnh
2. nh hng ca khng cn bng
3. nh hng mt dng in khng ng nht
Saturday, March 28,
2015
PGS.TS Le Minh Phuong
Energy saving
nh hng ca khng cn bngLi 0,4kV thng xy ra hin tng khng cnbng trong cc pha, iu ny lm tng tn tht trongli. Ta s dng h s khng cn bng kunbalance
2 2 20 0
23 (1 1,5 ) 1,5( )A B C
unbalanceA B C pha pha
I I I R RkI I I R R
Trong R0 in tr dy trung tnhRpha in tr pha
Saturday, March 28,
2015 PGS.TS Le Minh Phuong
Energy saving
Thc t rt kh o dng in trong cc pha v vyc th s dng gi tr trung bnh ca h s kunbalance.
Theo thc nghim, khi dng in pha lch so vidng in trung bnh 0,3-0,5 v R0/Rpha=1-1,5
H s kunbalance=1,15-1,55 (1,350,2) i vi liphn b ti dc theo ng dy,
H s kunbalance=1,050.05 i vi ti tp trung vphn ti 3 pha cn bng nhiu hn.
1 0,63L pk d
1,05 0,3unbalance pk d
Saturday, March 28,
2015
March 28, 2015
16
PGS.TS Le Minh Phuong
Energy saving
nh hng mt dng in khng ng nht: khi mt dng in khng ng nht trong cc ung dy ta cn phi tnh mt h s kN, thcnghim cho thy gi tr ny nm trong khong1,10,06. Nu l mt ng dy trc chnhNu l dy nhm (=2,82.10-8 m)
Nu l dy ng (=1,72.10-8 m)
2 2 2
2
W (1 ) 2,82W hd L unbalance Ntg k k k k LTU F
2 2 2
2
W (1 ) 1,72W hd L unbalance Ntg k k k k LTU F
Saturday, March 28,
2015 PGS.TS Le Minh Phuong
Energy saving
Nu c nhiu ng dy trc chnhNu l dy nhm (=2,82.10-8 m)
Nu l dy ng (=1,72.10-8 m)
F2 tng tit din cc ng dy trc chnhn- s ng dy nhm ng dy vi tit din khcnhau, nhn nng lng t 01 trm.
2 2 20,4 1
0,4 2 2
2,82W (1 )W
n
i ihd L unbalance N i
F Ltg k k k kTU F
2 2 20,4 1
0,4 2 2
1,72W (1 )W
n
i ihd L unbalance N i
F Ltg k k k kTU F
Saturday, March 28,
2015
PGS.TS Le Minh Phuong
Energy saving
Nu c ng dy cp cho ti 2 pha v 1 pha chiudi ng dy c th xc nh
L1- tng chiu di dy dn 1 phaL2-3 tng chiu di hai v ba pha phn nhnhLmain chiu di ng dy trc chnh
Bi tp
2 3 10, 44 0,22mainL L L L
Saturday, March 28,
2015 PGS.TS Le Minh Phuong
Energy saving
Phng php tnh tn tht in nng theo st pTn tht in nng c th biu din qua st p
w/W% %k u unU k
Saturday, March 28,
2015
Trong Kwu- h s t l gia tn tht in nng v tn tht in pKun- h s tnh n tnh khng ng nht ca ti ca cc pha
March 28, 2015
17
PGS.TS Le Minh Phuong
Energy saving
i vi ng dy c ti tp trung pha cui
Khi h s
2 220
2 2
Pr( )% 100% (1 )100%LP Q RP tg
PU U
02 2
Pr% 100% (1 ).100%LPR QXU tgU U
Saturday, March 28,
2015
Trong =X/R t s in khng v in tr dy dn (vi cp =0; vi ng dy trn khng =0.01:0.0125*F)
2
w/% 1k% 1u
P tgU tg
PGS.TS Le Minh Phuong
Energy saving
i vi ng dy c ti phn b dc ng dy
Khi h s
2 22 0
2 2
r( ) 100%P% 100% (1 )3 3
LP Q RP tgPU U
002 2
0
r100% 100%% (1 ) Pr (1 )2
L LL l PU tg dl tgU L U
2
w/% 2 1
k% 3 1u
P tgU tg
2
w/1k (1 0,25 )1u p
tgdtg
Saturday, March 28,
2015
PGS.TS Le Minh Phuong
Energy saving
Nu bit in nng truyn ti trn ng dy khi c th xc nh c cng sut cc i
Tn tht cng sut ln nht
Tn tht nng lng
axW
mdk
PTk
2% w /
ax ax2 1 2W . W
3 100 3dk dk dk u unbalance
m mpn
k k U k k kP P Tk
Saturday, March 28,
2015
w/ax ax w/
U%WU%100 100. .
um m u
dk
kP P kT k
axw/ w/
ax
%k 100 U%%
mu u
m
PP kU P
PGS.TS Le Minh Phuong
Energy saving
Bi tpXc nh tn tht cng sut trn 1 km ng dy A-90(r0=0.34/km; x0=0.4 /km), nu bit nng lngtiu th l 10MWh trong 1 thng (30 ngy), in p l380V. Cc thng s cn li tg=0.5; kdk=0.3;kunbanance=1.05; kN=1. Ti tp trung cui ngdy
Saturday, March 28,
2015
March 28, 2015
18
For our future
THANK YOU
FOR YOUR ATTENTION
Energy saving
Saturday, March 28,
2015 PGS.TS Le Minh Phuong