Mat ttong nhttng giai phdp dang dugc si dung khd phfl bie'n tren thfi gioi hien nay ma ngdnh dien Viet Nam cdn nghifin cttu dp dung la H6 thfi'ng gidm sdt va chdn dodn ky thudt lifin tuc
Trang 1Hd Ngi, 11-2005
V MOT SO VAN DE TRONG XAY DONG
HE THONG CHAN DOAN VA GIAM SAT KY THUAT
MAY BIEN AP LUC TRONG HE THONG DIEN VIET NAM
Trdn Ky Phdc: Viin Ndng lugng
Le Thi Thanh Hd: Dgi hgc Bdch khoa Hd Ndi
Tdm tdt:
Bdi bdo ndy nghiin cdu cdc phuang phdp chudn dodn vd gidm sdt ky thudt mdy biin
dp (MBA) lire Irong hi thd'ng diin (HTD) Bdi bdo cung dua ra gidi phdp cdu hinh sabd hi thdng chudn dodn ky thudt MBA lire phd hgp dieu kiin Viet Nam, ddng thdi nhdn dgng cdc vdn de kinh li-ki Ihudt cdn gidi quyet khi xdy dung he thd'ng chdn dodn ndy
Abstract:
Methods for monitoring and diagnosis of large transformer in power system are presented The paper also shows solution on configuration of Ihe monitoring and diagnosis system compiled with conditions in Vietnam, defines economic- technical problems to be solved in Ihe system design and installing
I DAT Ym DE
Cdc nhd mdy di?n - dac bifit cdc nha mdy difin cflng sudt Ifln - thttflfng dugc xay dung
fl nhttng noi gdn ngufln nang Ittgng so cdp nhu mfl than, mfi khi, ngufln nuflc, nhdm trdnh chi phi vjn chuyfin nhien li$u di xa va ban chfi tdc dflng tifiu cue cia chdt thai t i cdc boat dflng phdt dien dfin mfii tmflng dflng dan cu Dfii lai, ngufli ta phai xdy dung cdc duflng ddy tmyfin tai dfi dua difin ndng dfin cdc trang tam tifiu thu VI dien dp cdc mdy phdt thuflng Id 6,3; 10,5; 15,75; 38,5 kV nfin dfi tang kha ndng trayfin tai va giam tfln hao cflng sudt trdn dttflng ddy cdn ndng cao dien dp truflc khi tmyfin tai bdng mdy tdng dp Mat khac, dien dp cia tai thttflng thdp (khoang 127 V dfin 500 V dfli vfli tdi ha thfi'; 3 - 35 kV dfii vfii tai ttung the) nen fl cdc nut phu tai cdn dat cac may giam dp
Nhu vdy, trong he thflng dien mufin trayfin tai vd phan phfli di$n nang ttt nhd mdy dien den t?n hfl tieu thy mgt each hgp ly thuflng cdn phai qua hai, tham chi ba, bfln Idn tang, giam ap, vd MBA la mflt trong nhung phdn t i chi dao, khflng thfi thifiu, da dang vfi
chung loai va nhifiu vi sfl Ittgng trong HTD
Dfl tin cay vdn hdnh cia cac may bifin ap ndy fl mflt mic dfi nao dfl quyfi't dinh chdt lugng cung cd'p difin ndng cho he thfing difin qufic gia Su cfi MBA, dac biet cdc MBA luc (cd'p 110 kV trfl len cfing sudt lfin, thu&ng ttt 40 MVA dfi'n 250 MVA hodc cao hon), gay ra cdc tfin thdt Ifln vfi kinh tfi nfin nganh dien cdn tim kifim vd dp dung cdc giai phdp httu hifiu dfi bao ve MBA khfli cdc su cfi dfit xudt Mat ttong nhttng giai phdp dang dugc si dung khd phfl bie'n tren thfi gioi hien nay ma ngdnh dien Viet Nam cdn nghifin cttu dp dung la H6 thfi'ng gidm sdt va chdn dodn ky thudt lifin tuc trang thai MBA
Trang 26 VlftT NAM
Dfii vfli HTD Viet Nam so Iugng va cflng sudt MBA luc du kifin ldp ddt t i nay dfin nam 2020 theo Quy hoach phdt trien dien luc qufic gia giai doan 2000-2010 cfi xet dfin
2020 nhtt sau:
Bang 1 So lugng va tdng cong suat cae MBA du kie'n lap dat, so MBA/ MVA Cdp dien ap / Giai doan
SOOkV
220kV
11 OkV
2002-2005 11/5200 54/8815
192
2006-2010 7/3300 49/8189
334
2011-2020 17/19550 144/22313
Su cd MBA, dde bifit ede MBA luc (cdp 110 kV trd Ifin cdng sudt Idn, thudng tfi 40 MVA dfi'n 250 MVA bode eao hon), gdy ra cae tdn thd't Idn vl kinh t l xa hgi Nghifin cfiu
va dp dung cdc giai phdp dl bao vfi MBA khdi cde su cd dflt xudt, ndng cao ehdt lugng cung cdp difin ndng, giam tdn thdt vl kinh t l Id mflt trong nhfing nhifim vu uu tifin hang ddu cua ngdnh difin
Tuy nhifin, cho dfi'n thdi dilm ndy, nganh dien Vifit Nam chua cd dinh hudng ro rang trong linh vue chdn dodn vd gidm sdt ky thudt thifi't bi difin cao dp ndi chung vd MBA lue ndi rifing Cac phuong phdp bao vfi MBA lue hifin nay nhu bao vfi so Ifich, qud ddng, diu theo nguyfin tde "da rdi", ehua du bdo ede su ed cd thi xay ra Mflt sd cde su cd lien quan din MBA nhu nd sfi, su ed ngdn mach cufln ddy, diu khflng duge chdn doan trudc bdng cdc bifin phdp ndy
Rifing ro le khi trong mdt sd trudng hgp cd thi giup phdt hien cde khuylt tdt kem theo hifin tugng thodt khi rdt manh tfi MBA Khi dd vific cd ldp kip thdi MBA se ngdn ngfia khuyfi't tdt phdt triin thanh hu hdng Idn va ngdn ngfia vific dfing may do su cd Tuy nhifin, phuong phdp sfi dung ro le khi cd nhihig ban ehl nhdt dinh Nd ehi cho phep phdt hifin ede khuylt tdt da phdt triin du Idn va vi khdng nhdn dang dugc loai khi phdn huy tfi ddu MBA nfin khdng cd kha ndng cung edp eae thflng tin vl chung loai, vi tri cde khuyfi't tdt trong MBA
Do eac gidi ban vl vfl'n ddu tu, kit cdu ludi va phucftig thfic vdn hdnh nfin nhilu MBA trfin lu^ difin Vifit Nam budc phai vdn hanh vdi mdt cbl dfl qud tai nao dd Diiu nay, mdt mdt yfiu cdu phai ddnh gia kha ndng mang tai cua MBA; mdt khac, cdn phai ehdn dodn trudc duge cdc hifin tugng phdt triin su cd cue bfi thdnh su ed cua ca MBA trong diiu kifin vdn hdnh khdc nghifit hon so vdi dinh mfic ma MBA dfigc thifi't kl
III MOT SO GlAl PHAP X A Y DUNG HE THONG G I A M S A T V A CHAN D O A N
KY THUAT MBA N G A N H DIEN VIET NAM
3.1 C^c phirong phap chan doan ky thuat MBA hien dai
Hfi thdng chdn dodn va giam sat ky thudt MBA eung nhu cac thilt bi difin khdc la mdt hfi thd'ng edng nghfi dam bao cdc chfic ndng sau:
- Chdn dodn dugc tdi da cac tinh trang ky thudt trudc khi x^y ra su cd ddi vdi MBA, trfin CO sd dd cd k l hoach chii ddng hon trong bao dudng, sfia chtta vd thay thi MBA trfin ludi (Chfic ndng chdn doan)
Trang 3ttinh van hanh, trfin co sfl dfl cfl cdc giai phap van hdnh tfii uu cho MBA (Chttc nang gidm sdt)
He thfing chdn dodn va giam sdt ky thudt MBA dugc xdy dung ttfin co so mfit hodc mfit sfi cdc phttong phap phdn tich sau:
1) Phan tich nhiet do difim nflng nhdt cufln day (Winding hot-spot Temperature) 2) Phdn tl'ch khi phdn buy ttt ddu MBA (Dissolved Gas Analysis - DGA) 3) Phan tich dfi dm cud ddu MBA vd c i a gidy cdch dien (Moistore Analysis) 4) Phan tl'ch phfing difin cue bfi (Partial Discharge Analysis)
Dufii ddy la mfl ta so luge ve cac phugng p h a p nay
1) Phan tich nhifit dfl difim nfing nhdt cufin ddy (Winding hot-spot Temperature) Ban chdt c i a phuong phdp phdn tich nhiet dfl difim nflng nha't cufln day Id s i dung sfi lifiu do nhiet dfi lop ddu Ufin c i a MBA, phu tai ting thfli difim c i a MBA vd cdc dac ti'nh ky thudt c i a MBA dfi ti'nh ra:
a) Nhifit dfi difim nflng nhdt cua cufln ddy MBA (Nfi'u nhifit dfl ndy do dugc dfii vfii mfit sfi MBA thi khflng cdn tinh todn)
b) Tfic dfi vd m i c dfl lao hod c i a cdch difin
Trfin CO sfl dfl dtta ra cdc x i li sau:
a) Dtta ra cac canh bdo hoac tin hifiu di cat MBA ra khfli he thflng nfiu nhifit dfl c i a lflp ddu ttfin va/hode nhifit dfi difim nflng nhdt cufln day vuot qud gifli ban cho phep b) Ddnh gid tfic dfi lao hod do nhifit ttng vfii chfi dfi mang tdi hifin hanh va tufii thg tmng binh cfln lai c i a MBA Dfi ti'nh ra tflc dfl lao hod cufli c i n g cdn nhdn tfic dfl lao hod
do nhiet vd tflc dfl lao hod do cfl hoi dm trong ddu vd gidy each dien
c) Tren CO sfl nhiet dfl ddu, nhiet dfl cufln ddy va tflc dfl lao hod do va tinh dugc danh gid difiu kifin mang tai cua MBA vd dfi xudt chfi dfl mang tai hgp Ii c i a MBA
Tinh kha thi vfi ky thuat c i a phugng phdp nay Id khd ro vi da sfi cdc MBA trfin lufli hien nay dfiu dttgc trang bi cdc dfing hfl do nhifit dfi cdn thifit neu trfin Tinh kha thi vfi kinh tfi cung cung cfl thfi ddnh gid thflng qua hieu qua nhfl cdnh bao truflc hien tugng qua nhiet dfl cho phfip c i a ddu vd cufin ddy, cung nhu dfi xudt dugc chfi do mang tai hgp li vfi kinh
tfi-ki thuat c i a MBA va giup qud trinh gidm sat tufli thg trang binh cfin lai cua MBA Phuong phdp nay cfl thfi dp dung on-line (cung vfli he thfing gidm sdt chdn doan
chung) hoac off-line tuy theo vai ab c i a MBA ttong hfi thfing vd quy mfi ddu ttt cho phep
2) Phdn tl'ch khi phan buy t i ddu MBA (Dissolved Gas Analysis - DGA) Phttong phdp ndy dtta ttfin mfii tuong quan gitta hifin tugng sinh ra khi phan hu^ t i ddu vd cdc loai su cfi cue bfi trong MBA Uu difim c i a phttong phdp nay Id fl chfi cdc stt cfi dang phdt trifin cfi thfi nhdn bifi't dugc rdt Idu ttuflc khi su cfi nghifim trgng xay ra va truflc khi rg le khi tdc dfing
Thflng thuflng cdn thifi't hi do 4 loai khi H j , CO, Cfl, va Q H , Ngodi ra, cfl th^ phan
tich them methan (CH,), ethan (CjHj), dioxide carbon (CO,)
Dufli day Id mflt sfi vi du vi su tttong quan gitta khi xudt hien vd loai stt cfi cue bfi
trong MBA [2]:
- H,: Ddu hifiu cfl phflng difin cue bfl ttong MBA
- CO: Ddu hieu gidy each difin hi dun nflng
- Q H j : Ddu hieu cfl hfi quang dien (arc)
Trang 43) Phdn tich dd dm cud ddu MBA vd cda gidy cdch diin (Moisture Analysis) Vidu: mflt mfl hinh phdn tich dfl dm dua trfin cdc phep do sau:
- Dfl dm tuong ddi cua ddu
- Nhifit dfl tai cam biln dfl dm
- Nhifit dfl Idp ddu trfin
- Ddng tai
Cac sd lifiu ddu ra cua phuong phdp ndy la:
- Ham lugng nude dm cd trong gidy cdch difin (ti'nh trfin co sd dudng eong cdn bdng
dd dm theo Oommen vd Fessler)
- Hfi sd lao hod do anh hudng eua nude trong cdch dien (tinh trfin co sd ham lugng nude dm cd trong gidy cdch difin ).Hfi sd lao hod nay se duoc nhdn vdi hfi sd lao hod do nhifit dl tinh ra he sd lao hod cudi cfing
- Nhifit dd khdi tao bot khi Di dam bao an toan, md hinh ddnh gid thudng ddt trudc
khoang each giiia gia tri nhiet dfl dilm ndng nhdt eua cufln ddy vd nhifit dfi khdi tao bgt khi (vi du, khoang 70°C) Khi khoang each giam xudng thi mdt tin hifiu bao ddng se duge phdt
ra
4) Phdn tich phdng diin cue bd
Do va phdn tich phdng difin cue bd (PD) la ki thudt chdn dodn MBA thuflc loai phfic tap vd khd dua vao thue tl do cdc ban chi vl do vd xfi li tin bifiu PD do dugc Mfic PD khdng binh thfidng la ddu hifiu cua su xudt hien cac bgt khf, bui kim loai trong ddu, hdng cue bd gidy cdeh dien eua cudn ddy, Hifin nay ngudi ta thudng sfi dung phuong phdp sdng
dm vd phuong phap difin dl phdt hifin, do vd phdn tich PD
Phuong phdp sdng dm dua trfin hifin tugng xudt hifin sdng dm lan truyin trong mfli trudng ddu MBA khi xud't hifin PD Phucmg phap nay sfi dung cdc cam biln piezzoelectric hodc cap quang
Phuong phap difin phat hifin PD dua trfin vific sfi dung cdc mach tao tin hifiu do dugc mfli khi xud't hifin PD trong cdeh difin MBA
Ngodi ra, hifin nay trfin thi gidi dang nghifin cfiu va dfia ddn vao dp dung phuong phdp UHF vd phuong phdp do cde ddp fing difin mdi PhfiOng phdp UHF da dfigc sir dung khd thdnh cdng trong giam sat PD cdc tram cdch difin khi (GIS) - dang bude ddu dp dung eho MBA
3.2 Mdt sd giai phap xay dung he thdng giam sat va ch^n doan ky thuat MBA nganh dien Viet Nam
Nghifin efiu tdng quan cdc phfiOng phap gidm sdt vd chdn dodn ki thudt MBA vd tinh hinh vdn hanh bao dudng eac MBA nay trfin ludi difin Viet Nam ddt ra eac vdn dl cdn giai quyfi't nhu sau:
1/ Lua chgn cd'u hlnh vd chfic nang cua hfi thdng chdn dodn hgp Ii va hifiu qua dap ihig vai trd ciaa MBA trong hfi thdng va cdc rang budc vl vdn ddu tu So bd ddi vdi cac MBA trfin HID Viet Nam ed thi xem xet ede giai phap sau:
- Dd'i vdi MBA 110 kV: Do vai trd cac MBA ndy trong hfi thdng, gidi ban cdu hinh vdi chfic ndng phdn ti'ch nhifit dd dilm ndng nhdt eua cufln ddy MBA Cdu hinh ndy cho phip xde dinh nhifit dd dilm ndng nhdt cua cufln ddy MBA, tdc dd va mfic dd lao hoa cua cdeh difin MBA, tfi dd dfia ra cdc canh bdo hodc tm hifiu di cdt MBA ra khdi hfi thdng nlu
Trang 5va tflc do lao hod do vd tinh dugc cfi thfi ddnh gia difiu kifin mang tai c i a MBA va dfi xudt chfi dfl mang tai hgp li c i a MBA
- Dfli vfli MBA 220 kV: Ngoai phan ti'ch nhiet dfl difim nflng nha't c i a cufln day, dfli voi MBA 220 kV hfi thfing chdn dodn vd gidm sat cdn bfi sung c h i c ndng phdn tich khi phan huy t i ddu vd phdn tich do dm cua ddu vd gidy cdch difin Hinh 1 la cdu hinh hfi thfing cho traflng hgp nay Cau hinh nay cho phep xdc dinh loai vd vi tti khifim khuyfit cfi thfi ddn den stt co MBA Bfl difiu dp dttfli tai MBA cung Id dfii tugng gidm sdt chdn dodn theo cdu hinh nay do vai ttfl quan trgng vd dfl tin cay khfing cao c i a nfi ttong MBA
- Dfli vfli MBA 500 kV: Do vai tto quan trgng trong HTD Viet Nam, cdc MBA 500
kV khuyfin cdo nen van hdnh dufli su gidm sdt va chdn doan c i a mflt he thfing on-line vfii ddy du chttc ndng, t i gidm sdt nhiet dfl, dfi dm, khi phdn buy cho dfin do va phdn ti'ch phan bfi cdc phflng difin cue bfl vl lgi ich t i he thfing nay vttgt xa chi phi ddu ur thifit bi chdn doan
Rieng dfl'i vfli cdc MBA tdng dp fl cdc nhd mdy dien, tuy quy mfi cfing sud't vd vai ttfl cdc tfl mdy ttong hfi thfing ma xac dinh cdu hlnh hgp Ii, Itta chon mflt ttong 3 cdu hinh nfiu tren • * 2/ Phan tl'ch hieu qua kmh tfi - ky thudt cua vi6c dp dung he thfing gidm sdt va chdn dodn ki thuat mdy bifin dp HTO Viet Nam Tinh toan hieu qua cfl thfi dua trfin tttong quan chi phi dau ttt he thfing Chan dodn va gid thdnh MBA, hoac cfi thfi tinh todn ddy d i ding phuang phdp phan tich lgi Ich - chi phi trfin cg sfl cac sfi lieu ddu vao vfi gid ddu hi he thfing chdn dodn, tfin thdt kinh tfi ttt vific cat difin do su cfi dfit xudt khfing chdn dodn va du bdo kip thfli
_ 3/ He thfing gidm sdt vd chdn dodn ky thuat MBA cho ngdnh difin Vifit Nam phai dam bao cdc c h i c nang chung sau:
- Thu thap vd x i Ii sfl lieu van hdnh c i a MBA
Trang 6phan huy t i ddu,v.v ) ti'nh todn gid tti cac thflng sfl giam sdt va chdn dodn tinh ttang thuc tfi cia MBA
- Dat cdc gid tri nguflng cho cdc thfing sfi gidm sdt vd dtta ra cdc canh bao ve tinh trang MBA, phdt hien finh ttang nghifim trgng miflc khi su co xay ra thuc su
- Luu trtt dtt lifiu vd kfit qua phan tich cho tray cdp dinh ki ttt xa
- Dtta ra cac tm hifiu difiu khifin quat ldm mdt vd cdc thifit hi bao vfi MBA khdc Tich hgp thfing tin thfing qua mang LAN va WAN cia nganh dien, ve Idu dai nghifin cttu kha nang si dung mang khfing ddy WLL CDMA - 450 MHz cia vifin thflng dien luc
- Tich hgp thflng tin thflng qua mang Internet dfi cfl the tmy cap ttt van phflng Trang tam difiu dfl HTD quflc gia AO, trang tam difiu dfl cdc cdp vd khi ngttfli tray cdp
Cdc mfl hinh du kifin s i dung:
a) Mfl hinh nhiet dfl diem nflng nha't cufln day vd lao hod cdch difln: si dung mfl hinh lEC 60354 hoac IEEE C57.91
b)Mfi hinh phan tich dfl dm: si dung duflrng cong can bdng dfl dm theo Oommen vd Fessler, ti'nh he sfl lao hod do anh huomg cia nufic ttong cdch dien vd nhifit dfi khoi tao bot khi
c)Mfl hinh phan tich khi phan buy: si dung mfl hinh ttt IEEE C57.I04 hoac lEC
60599 [2, 3]
Tflm lai, xay dung bfi thfing gidm sdt vd chdn dodn ky thuat MBA thay vi nhap ngoai
Id cdn thifit (vi ngoai cdc li do kinh te cdn tinh dfin cdc ddc thu cia MBA va difiu kien van hdnh ttong HTD Viet Nam) va hodn todn kha thi Hifin nay, ngdnh dien Vifit Nam dang phfii hgp vfli cdc co quan nghifin cttu trong nuflc (Dai hgc Bdch khoa Ha Nfii, Vifin Nang Iugng, ) xay dung he thfing ndy va da co ban hoan thanh pha ddu cia dtt dn lien quan dfin mfl hinh phan tich difim nflng nhdt cufln day [4] Mfi hinh x i li sfi lifiu ve nfing dfi khi phdn buy dang dugc nghifin cttu xdy dung
Tdi liiu tham khdo:
[1] An Integrated System Approach al Commonwealth Edison Presentation at the
GE Energy Management Monitoring Conference, Nov 2000
[2] lEC 599 Interpretation of the Analysis of Gases in Transformer and Other Oil-filled Electrical Equipment in Service
[3] ANSIIIEEE C57.104 Guide for the Interpretation of Gases Generated in Oil Immersed Transformer
]4] Chuang trinh xdy dung he Ihdng chdn dodn gidm sdt ki thudt thii't bi diin cao dp ngdnh diin Viet Nam EVN- Ban KT Ihudt ludi diin - Tdi liiu ndi bd - 2001