_ Bdi bdo gidi thl$u t6ng quelk cdc phudngpimp dfnh vf sifdi trin di/dng ddy truyin tdi, tuy nhiin chi gidi h^n vdi cdc phiMng phdp aSr di/ng tfn hl^u So ludng tit hal Mu.. Cdc tin M4u
Trang 1E] KHOA HQC • CdNG NGHf;
long quan cp pifmm^h^r ^
DUA TREN TlN^HIED DD LfimiGYirHAI PHiA
Nguyin Xuin T£ing, Nguyin DCTc Huy, Nguyin XuAn Hoing V l ^
Tdm t i t - / _
Bdi bdo gidi thl$u t6ng quelk cdc phudngpimp dfnh vf sifdi trin di/dng ddy truyin tdi, tuy nhiin chi gidi h^n vdi cdc phiMng phdp aSr di/ng tfn hl^u So ludng tit hal Mu Cdc tin M4u do ludng ndy cd titfdd^ ddng b^ hda thdng qua hf thSng GK ho^c khdng dupic ddng b^ Phdn Clttg d\mg cda cdc thu^ todn ndy gidi thlfu kit qud md phdng 061 vdi m^t tuyin dUlfng ddy 220 kV
1 Gidi thi6u Chung
Cic dudng d i y truyin t i i
thudng cd chilu d i i Idn v i ddi khi dl
qua cac vung dia hinh ddi nui phdc
tap, dieu niy g i y nhilu khd k h i n cho
cdng t i c tim i ^ l m sU cd Do viy, vi^e
tfnh t o i n djnh vi chinh xic d i l m sued
tren dUdng d i y cd y nghia r i t Idn, rut
g i i m bdt d i n g ke n h i n cdng, v i t lUc
Cic dudng d i y truyen t i i vdi
cap dien i p t d 220 kV trd len thudng
dupc trang bi cic b i o v§ chfnh l i
chde n i n g b i o ve khoing eich va
b i o ve so lech dpe (nlu cd dudng
truyen b i n g thdng rdng) Thuc te cho
thay, chde nang djnh vj su cd trong
cac rdle khoing each b i o vi tri vdi
mdt mde dd sai sd tUong ddi Idn Cie
role so l&ch dpe hien dai da dupe tich
hpp them chde n i n g djnh vi sU cd v i
cd khi n i n g lam viec vdi dp chfnh xic
cao hdn, dieu niy la h o i n t o i n thue
t l vl eie rdle loai n i y thudng sd dyng
nguyen ly dinh vj sU cd dUa tren tfn
hieu do ludng t d hai dau dudng diy
Bii b i o n i y se gidi thi^u, lam rd
cac nguyen ly eo b i n d l djnh vj sU
cd dua tren tin hieu do ludng t d hai
dau dudng day Ndi dung ly thuyet
lien quan den djnh vj sU cd dUa tren
cie tin hieu do ludng ddng bd dupe
trinh biy d muc 2 va tiep theo myc 3
14 I Dien & D&i song
gidi thi$u cic v i n d l c i n xd 1^ khi tfn hi^u do ludng khdng ddng bO- Myc
4 se gidi t h i | u cic k i t q u i tfnh t o i n
md phdng d l chdng minh tfnh k h i thi ciia t h u i t t o i n
2 Dinh vi SU cd dUa tr6n tin hieu do Itfdng tfdng b6
Cic phuong p h i p dinh vj si/cd dua tren tfn hi^u do ludng ddng bO
cd t h i Sd lupc p h i n loai theo:
• Sd dyng cie tin h i | u ddng v i
i p t a i t i n s d c d b i n { 5 0 H z i
• Sd dyng tin hi^u sdng Ian truyin (traveling-wave) t i n sd cao Phuong p h i p sd dung tin hieu sdng Ian truyin, cho tdi thdi d i l m
h i i n tai, dupc d i n h g i i l i phUdng
p h i p ed do chfnh xic cao (sai sd cd the chi trong pham vi mdt k h o i n g cdt, khoing 300 m), tuy nhlfin phuong p h i p n i y ddi hdi p h i i dau t u cic t h i l t bj chuyen diing {cie t h i l t bj
do xung ddng v i i p , cic p h i n m I m
xd ly tin h i i u ri^ng ) Chinh vl cic han e h l n i u trdn nen phUdng p h i p nay chUa dupe trien khai rOng rai, do
do se khdng gidi thieu chi t i l t trong bai b i o niy
2.1 Gidi t h i ^ u v l t h i l t bj GPS Tin hi^u do ludng tai hai d i u dudng d i y cd t h i duoc ddng bd v l
m i t thdi gian n l u cic tram dupc trang bj ddng hd thM gian t i / ddng
bd thdng qua tin hieu GPS He thdng GPS bao gdm n h i l u v$ tinh (khoing
30 v$ tinh v i o thdi d i l m n i m 2007 [1 ]), c i c v^ tinh d i u dUpc trang bj cic ddng hd do chinh xic cao vdi sai so
cd ±0,5 MS- N l u qui ddi ra gdc dO dien thi sai sd n i y tUdng dUdng vd^ chi
±0,009° trong mdt chu ky 360°
2.2 OInh vi si/ c6 dUa trin tfn hi6u sdng Ian truyin
Khi S I ; cd x i y ra tai mdt dilm
t r i n dudng d i y t i i dien, se giy ra cic dot b i l n v l ddng va i p Cic sdng ddng, i p ddt b i l n nay se Ian truyen trSn dudng d i y c i v l hai phfa vdi tdc dd Ian t r u y i n sdng xap
xi tdc dd i n h s i n g Khi sdng Ian truyin di tdi mot
d i u dudng d i y se gap d i l u kien bi^n thay ddi (thay ddi eiia tong trd), do d6 mot p h i n cda sdng n i y se phin xa trd lai v i mdt p h i n tiep tyc Ian tmyln
di t i l p
Sd do bleu dien qua trinh phin
xa, khue xa eQa cic sdng Ian truyin
t h i hien tren Hinh 1 DUa theo chinh l^ch thdi gian gida tfn hieu thu di/dc tai hai d i u (At) h o i n t o i n cd t h i xic djnh dupc vi trf diem sd ed bing phUdng trinh (2.1)
Trang 2l-c*M
x =
2 (2.1)
Trong dd:
x: khoing eich d i n d i l m sy cd
/: tdng chilu d i i dUdng d i y
c v i n tdc i n h sing {299,792 m/s)
D i e d i l m cCia phuong p h i p niy:
• Phii ed cic t h i l t bj ghi tfn h i i u dupe ddng b^ thdi
gian vdi dd chfnh xic cao, ehl mdt sy sai l^eh r i t nhd v l thdl
gian cd the d i n tdi sai sd Idn v l khoing eich tfnh dUdc
• Phan m I m p h i i ed k h i n i n g ddng bo hda tfn hidu,
loc nhieu v i trich x u i t tfn hi&u mong mudn Die biet vdi
cac SU cd g i y ra do s^t cd the g i y c i c nhieu dien t d i n h
hudng d i n dd chinh x i c eua ph^p Ipc tfn hiiu
Mdt sd nghien cdu khic cung da d l xuat tdi vi&c sd
dyng tin hi&u p h i n xa gida hai l i n l i i n t i l p tai mdt d i u
dudng d i y vdi nguy&n ly tinh t o i n h o i n t o i n tuong tu
Tr?mA
hi^n.Tuy nhiin, cic t h u i t t o i n n i y khdng t h i cho k i t q u i chinh x i c b i n g phUdng p h i p sddyng sdng Ian truyin
TCiy theo sd lupng tin hi§u do ludng sin cd m i t h u i t
t o i n cd t h i chia ra:
• Djnh vj sy cd dya tr&n tfn hi&u do ludng d i y du t d
hai d i u {do ludng d i y du ch ddng di^n v i di&n i p )
• Djnh vj SU cd dua tr&n tin hi&u do ludng khdng
d i y du t d hai d i u (tin hi&u do ludng t d mdt d i u cd t h i chi
l i d d n g d i & n h o i c d i & n i p )
• Ngoii ra cung ed t h i p h i n loai t h i m tuy theo vi&c t h u i t t o i n ed c i n sCf dung d i n sd l i i u v l tdng trd eua dudng d i y hay khdng
Thuat toan dUdc gidi thi&u chi t i l t trong b i i b i o nay
l i dya tr&n thdng tin do ludng d i y dii t d hai phfa dudng diy, cac trudng hpp edn lai sd dyng eich suy l u i n gan tUdng t u
X&t sU cd x i y ra tai d i l m F, each tram A mdt khoing la
X {%) tren dudng d i y AB nhU trong Hinh 2
A / B
* - L f e - <?.:5?
G>-Tr^mB-r
Hinh 1 Sulan truyen sdng trin dudng day
2.3 Ojnh vi sd cd dUa tren tin hieu tan sd cd b i n
50 Hz
Thuat t o i n djnh vj sU cd dUa tren cac tin hieu ddng
v i ap d tan sd cd b i n 50 Hz tUdng ddi ddn g i i n va de thue
-0
Hinh 2 Dudng day bi sUco
Sd dd thay t h i ddn gian {bd qua tong dan) ciia dudng
d i y tren trong trudng hdp sUcd nhutren Hinh 3
Bi
Hinh 3 Sad6 thay thi cua dudng ddysUco
Ddng dien va dien i p {/^ & ij, [U^ & U^ do tai hai tram
dupc dong bd ve mat thdi gian
Dien apUptai diem sU coed the tinh theo:
'^F=U,-l,'x''Z„ ,2,2) U,-U,-I,'(\-xrZ^ ,2,3,
trong do Z^ la tong trd ciia toan bp doan dudng day AB Trd hai phUdng trinh cho nhau:
C / , - f / j + / , * Z o = x « Z o • ( / , + / , ) ,2.41
Khoing each d i n d i l m sU cd dupc tinh ra theo phuong trinh:
,_c/,-iy,+/,'z„
^D'^^A+'B) (2.5)
Bien <t OtH songl ig
Trang 3El KHOA HQC CdNG NGHf:
Phuong trinh t r i n cd t h i i p dyng cho mpi trudng
hpp sy cd Tuy n h i i n , tCiy theo d?ng si/ cd m i li/a chpn
td hpp ddng dl^n v i d l | n i p thfch hpp Vf dy, vdi sy cd
Cham d i t mOt pha (N'") thi d i | n i p sd dyng l i ciia pha A,
tuy n h l l n ddng d l | n dua v i o tfnh t o i n c i n p h i i bii t h i n h
p h i n t h d t y khdng Trong thyc t l , r i t khd xic djnh dOng
di&n khing t h d t y khdng cOa dUdng diy, do dd vi&c tfnh
t o i n h$ sd bii ddng thd t y khdng s i khdng chfnh xic v i
cd t h i g i y sai sd cho p h i p djnh vj
D l t r i n h trudng hpp niy, nhilu nghiln cdu d l xuit
sd dung c i c t h i n h p h i n ddng di$n v i d i | n i p thd t y
t h u i n hoic nghieh (tfnh t o i n dya t r i n t h i n h p h i n thd t u
nghjch chi i p dyng dUde vdi cic sped khdng ddi xiifng)
Phuong p h i p djnh vj sy cd dda theo tfn hl$u do
ludng ddng bO t d hai d i u dudng d i y cd Uu d i l m hon so
vdi ehl diing tin h l | u t d mOt d i u :
Khdng bj i n h hudng ci^a tdng trd ngudn
Di$n trd tai d i l m sp cd khdng xuit hi$n trong
phuong trinh 2.4, do dd khdng g i y i n h hudng d i n dO
chfnh xic ciia k i t q u i djnh vj sy c6
3 Dinh vi diia tr£n tin hl^u do lUdng khdng ddng bO
Vi&e ddng bd tin hi&u do ludng chi ed t h i thuc h i i n
duoc khi cie tram d hai d i u dudng d i y cd sd dyng c i c
ddng ho GPS, tuy nhi&n trong thuc t l v i n edn n h i l u tram
khdng dUpe trang bi loai thiet bi niy T h u i t t o i n dUpe
gidi thieu trong muc n i y se trinh b i y phuong thdc d l t u
ddng bp lai cic tin hieu, phyc vu viec tinh t o i n djnh vj vj
tri d i l m sued
D i l m CO b i n eiia eie t h u i t t o i n n i y d i u dUa tr&n
ring budc l i dien i p tfnh d i n d i l m su c6 t d hai phfa p h i i
b i n g nhau
Trong t h u i t t o i n nay cd d l cap tdi khii niem gdc
ddng bd 6 gida cic tin hieu do dupc Trong trudng hop cic
tin hieu dupe do ddng bd chinh xac thi gdc d=0, ngupe lai,
gdc 6 se khic khdng v i t h i hi&n mde dd khdng ddng bO
gida eie tfn hieu do duoc trong mdt chu ky 360"
Vdi g i i t h i l t ve gdc d nhu viy, eie g i i trj dien ap v i
ddng dien tai mot phia can dUde ddng bd lai thdng qua
gdc d, hay ve mat t o i n hpc cie tin hieu n i y c i n n h i n vdi
toan t d e* {tUdng dUdng vdi viec dich pha tin hieu di mdt
gdc 6), sau dd h o i n t o i n cd the i p dung phuong p h i p
tinh toan n h u d i de cap trong myc 2.3
Cy t h i , dien i p v i ddng di&n dUa vao cic phuong
trinh 2.2,2.3,2.4 & 2.5 se thay doi nhU sau:
• Phi'a tram A: U^ & 1^ (gii t h i l t tin hieu tai tram A duoe
chpn l i m gdc tham chieu)
Ph\atramB:Ug'e'^&l/e'^
PhUdng trinh 2.4 bay gid ed dang nhu sau:
16 I Dien Jk D&i song
-x*Z„*(/,+/^V*) (2.6)
trong phuong trinh 2.6 thi cie g i i trj ddng v i i p d i u l i cic d^l tupng phdc
Phuong trinh 2.6 cd hai i n sd c i n tim l i gdc ddng bO
v i v| tri d i l m si/ cd {6 & x} 0 1 t h u i n t i | n cd t h i sd dyng
b i l n ddi e^=cos{6)+jsin(6) trong cie tfnh t o i n
Sip x i p phuong trinh 2.6 t h i n h hai phuong trinh
r l i n g cho p h i n thyc v i p h i n i o cOa cic sd phdc, ta cd h$ phuong trinh vdi d?ng sau:
F^iV/,I/,Vs;I/,Zo,^inS,'^osS;x)=0 (2.7) F^(V/J/,Va;J/,Z^;smS;cosS;x)=0 (2.8)
Giii h i phuong trinh n i y theo phuong p h i p loai trii
d i n c i c b i l n , sau khi loai trd b i l n x thi edn lai phuong trinh c i n g i i i l l l n quan d i n gdc d dudi d^ng:
A'sind + B'co$6^C=0 {2.8)
D i y l i dang phuong trinh cd b i n trong t o i n hpc v i
cd t h i g i i i b i n g n h i l u phUong p h i p , trong do pho biln
n h i t l i sd dyng phUdng p h i p l i p Newton-Raphson [2] Sau khi gdc ddng bO 5 d i tim dupc thi hoin toin c6
t h i xac dinh khoing eich d i n d i l m sy cd b i n g eieh thay
v i o phuong trinh 2.7 h o i c 2.8
Thuit t o i n n i y don g i i n v i cd t h i dupe thuc hi&n dyng c i c ngdn ngd l i p trinh nhu MATLAB Ket qui tinh
t o i n dinh vj sy ed t h i hi&n dO chinh xic tuong ddi cao,
k l c i vdi cie sp cd cham d i t , it phy thudc v i o dien trd tai
d i l m si/cd.Tuy nhi&n ed mOt v i i y l u t d can quan tam nlu
i p dyng trong thpe t l :
• Cie tin h i | u ddng d i l n v i di&n i p cd the trich xuit
t d c i e cic b i n ghi sped ciia role, do dd phucmg phip niy
h o i n t o i n cd t h i i p dyng trong thue t l
• N l u dudng d i y sd dung cic b i o v i vdi thdi gian
t i c ddng nhanh thi cd t h i c i c tfn hi&u q u i do trong dang sdng ddng n g i n mach v i di&n i p cd t h i ehua t i t
h i n , ehua dat trang t h i i xic l i p , khi dd k i t q u i tinh toan
ed t h i cd sai sO Idn O l t r i n h trudng hpp niy, mdt s6 nghi&n ciifu x i c djnh gdc ddng bd dua tr&n cic dai lupng
t r u d c s u c d t 3 ]
• Mde do chinh xic eua t h u i t toan van phii dua vio
dd chfnh xic ciia tdng trd dudng diy, tuy nhi&n tdng trd
niy thudng r i t khd d l cd t h i tfnh t o i n chinh xic, tril khj
cd cie bien p h i p do true t i l p tat hi&n trudng [4] Mot so
t i c g i i d i trinh b i y k i t q u i nghien cCfu v l vi&c coi tdng trd dudng d i y chi l i dai luong trung gian trong qua trinh tfnh
t o i n v i khdng can sddyng d i n gia trj tdng trd thuc M6ts6 nghien edu khic coi tong trd dudng d i y l i mot b i l n trong
q u i trinh tfnh t o i n v i k i t q u i eudi ciing dua ra khdng chi
Trang 4KHOA HQC - CdNG NGHf: Q
Pri d i l m su ed, gdc ddng bO m i edn bao gdm c i g i i trj
trd ciia dudng d i y tinh t o i n dupe [5], [6]
I M d phdng k l l m chiSfng
Md phdng dupe thpc h i i n di k i l m chdng t h u i t
t o i n da de cap tdi trong myc 3 (tin h l i u do ludng hai d i u
khdng dupc ddng bd), trUdng hpp tin hi^u dupc ddng bO
sin thdng qua h& thdng GPS chi l i mOt trudng hpp con vdi
gdc dong bd 6=0
Md hinh md phdng l i t u y i n dudng d i y 220kV tUOng
t u nhu Hinh 2 vdi cic thdng s6 nhu sau:
TramA:Zngu^„=d[50^rn;
TramB:ZnBuAn=5|^QVOJ
Chilu dai dudng d i y : 100km
Tdng trd thd t u t h u i n ciia dudng diy: 8+j30{n)
• Tdng trd t h d t u khdng cua 1 km dudng diy: lay
b i n g 1,5 l i n tdng trd thd tU t h u i n
Tan sd lay m i u tfn hi&u: 20 miu/1 chu ky
Trinh tUthUc hien md phdng:
• Dien trd tai diem sU cd dupc md phdng vdi cie
g i i tri 50 & 300
Phan mem PSCAD diiac sd dung de md phdng,
tao sU ed, ghi lai cie tfn hieu ddng v i i p t d hai dau dudng
day De tao ra su do ludng khong ddng bp thi tin hieu thu
duoc s& dupc cd y l i m l&ch di mdt gdc 18°
Vj tri diem sy cd g i i t h i l t tai 30% dudng day
(tUdng dng vdi vj trf 30km tdtram A)
• Cie tin hieu ddng v i ap n i y sau dd se dupc xd
ly thdng qua t h u i t toan v i l t b i n g MATLAB d l tim ra gdc
ddng bd va vj trf diem sU cd Tfnh t o i n dUa tr&n t h i n h
phan t h d t u t h u i n eua ddng dien v i di&n i p
Hinh 4 va Hinh 5 the hi&n ket q u i tinh t o i n vdi trUdng
hpp vj tri d i l m sU cd l i 30km v i gdc ddng bd cd y tao ra la
18°, dien trd tai diem sU cd la 5 0
H\nh5.Vitrfaiimsi/c6{R=50)
Hinh 6 v i Hinh 7 t h i hi&n k i t q u i tinh t o i n khi thay ddi kjeh b i n vdi di&n trd tai d i l m sued t i n g tdi 300
K«( qua Unh Io«n goc dong bo
1 8 1
18 08
18 06
g 18 04
1 '*•"
J "
1796
1794
ll 1 Goedongbolh
(1
l|
1
1 • / "
!''
uc i« (IS do) 1
•
•
3 4 0 3 6 0 3 8 0 4 0 0 420 440 4 6 0 4 8 0 5 0 0
Hinh 6 Gdc dong bo tinh todn ({\=30 Ci)
Kei qua tiVi loan khoang cacn loi diem su ca
Hinh 4 Gdc dong bo tinh todn {Ri:=5 Q)
Hinh 7 VitridiimsUc6iHf=30O)
Cie ket q u i md phdng ehi t i l t hon nda deu the hi&n rang:
• Thuit t o i n tinh toan gdc ddng bd cho dp chinh xac cao mac du tfn hieu dUa vao xd ly l i tfn hieu dupc lay mau rdi rae vdi tan sd khdng cao {20 mau/1 chu ky)
Dien & D&i song\ \j
Trang 5E] KHOA HQC - CdNG NGHf:
• Vj tri d i l m sy c6 dupc djnh v| vdi dO chfnh x i c
v i h i u nhu khOng phy v i o dl$n trd t^l d i l m si/cd
5 K A l u f n
Bii b i o trinh biy tdng quan v l hal phUdng thdc
djnh vj si/cd trong h | thdng dudng d i y truyin t i l dya
t r i n tin hl|u do lUdng dupc c i t d hai d i u
Phuong p h i p sddyng tfn hl^u sdng Ian t n j y i n cd
dO chfnh xic rit cao, tuy nhlln cin phii d i u t u t h i m cic
t h i l t bj v i phin m I m chuyin dyng
Phuong p h i p sd dyng tfn ht$u d t i n sd co b i n
50 Hz don g i i n har\ c i v l m i t t h u i t t o i n v i t h i l t bj,
nhung cd h^n c h i v l dO chfnh xic so vdi phuong
p h i p dpa theo tfn h l | u sdng Ian truyin n&u t r i n Tuy
nhlln, so vdi phucmg thdc djnh vj dua t r i n tdng trd,
do ludng t d mdt phfa thi phUong p h i p n i y cd dd
chfnh xic dupc c i i thi^n d i n g k l , k l c i trudng hpp
cd sy cd cham d i t qua d l | n trd trung gian
Cic t h u i t t o i n sd dgng tfn hi^u do ludng t d hal
d i u h o i n t o i n ed t h i i p dyng vdi c i nhdng dudng
d i y m i h& thdng b i o v^ khdng cd p h i n thu n h i n ,
ddng bd tfn hieu b i n g GPS
Do cic role ngiy nay d i u lUu trd dupc cie b i n
ghi sued n&n s& h o i n t o i n k h i thi d l t u v i l t eie p h i n
m I m t u ddng thue hi&n vi&c xd ly tfn hi&u, tfnh t o i n
i^nh vj su cd dUa theo eie b i n ghi sued niy
T A I Lieu THAM K H A O
1 Saha, Murari IVIohan, Izykowski, Jan Jozef,
Rosolowski, Eugeniusz Fault location on power
networks s.l.: Springer, 2010
2 Unsynchronized two-terminal fault location
estimation Novosel, D, et al 1, s.l.: lEEETransactions
on Powder Delivery, 1996, Vol 11
3 A practical approach to accurate fault location
on extra high voltage teed feeders R K Aggarwal, D V
Coury, A T Johns v i A Kalam s.l.: IEEE Transaction
on Power Delivery, 1993, Vol 8
4 Measurement of line impedances and mutual
coupling of parallel lines Ulrich Klapper, Michael
Kriiger, Wolfgang Wurzer s.l : Relay Protection
and Substation Automation of Modern EHV Power
Systems, 2007
5 Non-iterative algorithm of analytical
synchronization of two-end measurements for
transmission line parameters estimation and fault
location Pawel Oawidowski, Jan Izykowski, Ahmet
Nayir s.l.: 7th International Conference on Electrical
and Electronics Engineering (ELECO), 2011
6 An accurate fault location algorithm for
two-terminal transmission lines combined with parameter
estimation Renfei Che, Jun Liang, s I : Power and
Energy Engineering Conference (APPEEC), 2009
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