S KHOA HOC CONG NGHf Nghien cuu anh huang cua cac nha may thuy dien nho Oen che Op van banh va chat luong Oien nang Inoi Oien Oja phuong ^TRjNH VAN HUNG, ^PHAM VAN HOA ''''£)cf/ hoc Cong Nghiep Ha Noi; ^[.]
S KHOA HOC - CONG NGHf: Nghien cuu anh huang cua cac nha may thuy dien nho Oen che Op van banh va chat luong Oien nang Inoi Oien Oja phuong ^TRjNH V A N HUNG, ^PHAM V A N HOA '£)cf/ hoc Cong Nghiep Ha Noi; ^Dai hoc Dien IUc Gidl THIEU TOM TAT Trong tQdng lai cac ngudn nang iQdng tai tao (NLTT) se ddng vai trd cang Idn, sd dd ngudn Thuy dien vQa va nhd (TDN) dQdc danh gia la ngudn cd tiem nang Idn nhat d nUdc ta, cd vai trd quan trpng va anh hudng nhat djnh den chat iQdng dien nang cua ludi dien qua trinh lam viec theo mua Ngoai TON cd mQc tham nhap vao he thdng cang Idn chung cd the se cd anh hudng dang ke den cau true iQdi dien cung nhu che dp van hanh, tdn that cdng suat cua he thdng cung cap dien dia phQdng Bai bao se trinh bay mdt thuat toan, phUdng phap tim diem md tdi Qu cac mach vdng, phan tich va iQa chpn cac phQdng thQc van hanh hdp ly de tdn that dien nang nhd nhat, ddng thdi danh gia anh hQdng cua cac ngudn TON den chat iQdng dien nang cua iQdi dien phan phdi TrQde tinh hinh nhien lieu hda thach cang can kiet, viec tim hieu d i n h gia dung mQc de khai thac hieu qua ngudn NLTT, dd cd ngudn TON la that sU can thiet de dam bao phat trien ben vQng Cac nha may Thuy dien nhd d nUdc ta chu yeu tan dung cdt nudc tQ khoang 10m den 200m, 300m, iQu lUdng qua cac td may tQ vai mVs den hang tram trials Viec huy ddng ngudn TON tai chd vao cac gid cao diem iQdi dien da gdp phan giam ap iQc thieu ngudn nghiem trpng cua he thdng dien Qudc gia nhd mua mUa da sd cac nha may dUdc huy ddng cdng suat cao vdi thdi gian dn djnh, tham chi phat dien vQdt san iQdng thiet ke Viec huy ddng cac ngudn TDN rat cd y nghTa viec tan dung ngudn nQde de san bang bieu dd phat cua he thdng va giam nhien lieu sii dung cho cac nha may dien sil dung nhien lieu Tuy nhien cd nhQng nha may cd cdng suat rat nhd chi phat dien dQdc vao mua mUa, tham chi dQng hoat dpng vao mua khd, cac TON cung an chQa nhieu rui ro van hanh he thdng nhU: - Oa sd thuy dien nhd khdng cd hd dieu tiet nen khai thac vao mua khd la khd khan (mua phu tai tang cao), neu nhieu nha may ddng loat dQng phat se gay thieu hut mdt iQdng cdng suat Idn dja phQdng - Hau het cac nha may d xa tam phu tai nen dau ndi iQdi khd khan va gay tdn that truyen tai Idn; viec da dang chung loai thiet bi cung gay bat ldi quan ly van hanh va du phdng thiet bj SQ chenh lech dien ap cudi ngudn d cac che dp phat va dQng may cd the gay anh hQdng den chat iQdng dien ap tren iQdi dien - Cdng suat phat cua TDN thQdng cd djnh pham vi dem Cac thuy dien 16 Dien dt D&i song KHOA HOC - CONG NGHf: Q hoat dpng theo mua rd ret (mua khd - khoang t h i n g va mua mUa khoang thang) Trong qua trinh van hanh, cac TON thudng dUPc Uu tien phat theo bieu dd b i t budc - theo lUdng nUdc de tan dung tdi da cdng suat phat cua chung Khi dd ddng cdng suat tren lUdi dien se thay ddi neu cdng suat cua TON so sanh dUdc vdi tdng cdng suat phu tai cua xuat tuyen Oieu cd anh hudng nhat dinh den tdn that cdng suat tren iQdi dien, iQdng tdn that tang hay giam se phu thudc vao che dp hoat ddng cua phu tai va dSc diem phat dien cua TDN dQdc chat iQdng dien nang va cd ten that cdng suat thap nhat Xet trudng hdp mdt ludi dien cd ket ndi nha may TDN nhU hinh Trong hinh tdng chieu d l i cua xuat tuyen la I (km), chieu dai tQ phia t r a m bien ap ngudn den TON la g (km) Cdng suat phat cua TON la S^,, = P^,, + j Q ^ , , (kVA), cdng suat phu tai la S.^ = P^ -i-jQ.^ (kVA) Is Oe phan tich anh hQdng cua ngudn TON den phQdng thQc van hanh iQdi dien can phai tinh toan cac che dp khac trong dieu kien chpn diem md mach vdng hdp ly Xuat phat tQ c i c van de neu tren, bai bao se de cap den viec xay dung mdt thuat toan cho phep xac dinh dUdc mdt cau true ludi dien trung ap ket ndi c i c nha may TDN phu hdp vdi cac che dp phat cdng suat cua Thuy dien va che dp cua phu tai Tieu chi cho viec xac dinh cau true la: - Tan dung het ngudn nUdc cua TDN; - Ludi dien hinh tia, tdn that cdng suat la nhd nhat; - Chat lUdng dien nang iQdi dien dQdc cai thien sau tai cau true TON THAT CONG SUAT TRONG LlJdl D l f N KHI CO T D N He thdng dien dang van hanh, gia thiet dieu kien thiet bj va thao tac nhu nhau, dd phQdng thQc van hanh cd ban la phQdng thQc dam bao Tai (T) tl- - Viec du bao ngudn nUdc cua hau het nha may deu bj ddng khdng cd hd dieu tiet Vdi mdt vai nha may, dieu khdng quan trpng, nhQng he thdng cd nhieu nha may vdi tdng cdng s u i t du Idn se gay anh hUdng lap phUPng thQc van hanh mat can bang ngudn - tai ma khdng dUdc dQ bao trQde - Khi ket ndi iQdi dien, mdt p h i n cua iQdi dien se khdng cdn la hinh tia truyen thdng Tuy nhien vi cac ly ky thuat chung van dUdc phan doan b i n g cac DCL de van hanh hinh tia Dieu gay mdt sd khd khan nhat djnh cho ngUdi van hanh phai xac dinh dUPc cau true ludi dien hdp ly sad cho van khai t h i c dQdc het ngudn nudc cua TDN, tdn that iQdi phai nhd nhat va dam bao dQdc chat I Qdng dien nang Do dd cdng tac dieu dp lUdi dien, viec tinh t o i n phan bd cdng suat, tim diem md mach vdng, chpn cac phQdng thQc van hanh iQdi dien va nghien cQu anh hudng cua cac ngudn TON ndi vao iQdi dien d mua khd va mua mUa ddng mdt vai trd quan trpng viec khai thac triet de ngudn thuy nang, cai thien chat iQdng dien i^-^ Nguon (N) TDN _gjgn •>l \< Lkm Hinh Ludi dien phan phdi cd TDN Khi cd ket ndi nha may TDN, vdi cdng suat phat cua TDN la S.^^^ thi tdn that cdng suat tren ludi dien se bao gdm phan: - Tdn that cdng suat ke tQ vi tri ngudn den vj tri dau ndi TON; - Tdn that cdng suat tQ vj tri TON den tai • Dodo: '^Z ~ '-^NJTDN T (P^ rg(Pr "TDN) "*" '-"TDN_T • "*" yjiT ^2 ^TDN) P.^+Oj •rg + ^jjf^.rQ-g) + O r + PTDN + QTDN ' 2Pr PTDN " (1) ^QTQTDM) U^ r{l-g)iP;-+Qr) ^APj=: u- ^T ^ ~T ' V TDN ^ ^n -IPP -IO o vdi R = r.l lii cdng thQc tren, ta cd the phat trien len cdng thQc tinh toan tdn that tren dQdng day trQdng hdp tdng quat cua mdt he thdng phan bd cau true hinh tia cd nhieu xuat tuyen ket ndi nhieu nha may TDN Cdng thQc tinh tdn that cdng suat tdng quat tren dQdng day dQdc viet lai nhQ sau: APz=ItU' P^+0'+(p- +0^ -2P P -20 1- (2) Trong dd: n la tdng sd nut he thdng; R la tdng dien trd cua cac nhanh tinh tQ ngudn den vi tri dat TON (U); U la dien ap day cua iQdi dien; P.^ la cdng suat t i e dung cua tai tai nut thQ i; Q.^: cdng suat phan khang cua tai tai nut thQ i; P.^^.: cdng suat Dien dt D&i song 17 KHOA HOC - CONG NGHE tac dung cua TDN tai nut thu i; Q.^,^^^: cdng suat phan khang cua TDN tai nut thQ i vdi Y^^^ ^^ la tdng dan ndi giOa nut i v l nut k (1/Q); U^ va U^ la dien ap tai nut i va k tudng Qng (kV) Theo (2) TDN tham gia phat cong suit, gia tri mpt budc lap cua bai toan phan bd cong tdn that cong s u i t se thay ddi Tuy theo cong suat phu suat thdng thudng, neu gia tri cong s u i t phat cua tai va cong s u i t phat cua TDN, gia tri tdn t h i t se mpt may phat d ngoai cac gidi han tren hoac dudi thay ddi, neu van hanh hdp ly, gia trj tdn that (2) thi bai toan phan bd cong s u i t can p h i i dUdc tinh luon cd tinh hudng ma tdn that cdng suit dat gia tri toan lai, theo dd cong s u i t cap nhat mdi se la nhd n h i t [5] Tuy nhien xet pham vi cua mot cong s u i t d gi6i han cua may phat TrQdng hop HTCCD rpng Idn, de khai thac tdi da cong suit TDN va ddi vdi cac may phat TDN, xay tinh hudng dam bao chat luPng dien nang c i n phan tich chi tiet cong s u i t p h i t cua TDN vUpt qua cong s u i t thiet c i c rang bupc theo dieu kien van hanh cu the ke cua may phat (P ^), luc dd cong s u i t cap nhat bai toan phan bd cong s u i t cd the se dUpc M O HINH T O A N H O C BAI T O A N V A N lay chinh bang cdng s u i t P ^, nhUng van phai dam H A N H HTCCD CO K E T NOI T D N bao cac yeu c l u ve tieu chuan phat ndng va gidi Theo quan diem toan hpc, viec xay dUng bai toan han an t o i n cua m i y phat van h i n h lien tuc van hanh hdp ly he thdng cung d p dien cd xet de'n khoang thdi gian cho phep Khi dd de dam cac nha may TON cd the dupc xem la bai toan tdi Qu bao can bang cong suat ludi dien theo md bao gdm ham muc tieu va cac rang buoc can bang va hinh (5) thi p h i n cong suat phat tQ phia iQdi se rang bupc khdng can bang Vdi muc tieu la tdn that dQdc giam bdt, gdp phan tiet kiem dien nang cho cong s u i t mang dien cd TON II nhd nhat va iQdi dien Qudc gia Neu cdng s u i t phat cua TDN m l didu kien c h i t lupng dien ap luon nam pham vi cho phep vQdt q u i gidi han P^^., va Q^^,, ~ thi cd the tha'y rang phUPng trinh (2) cd rat nhieu gia trj thudc vao che dp hoat ddng cua phu t i i , che thuy van, lUdi dien hien hanh Ham muc tieu tdn that cong s u i t nhd nhat: ^ TDN-max TDN TDN-min TDN /• = IA/^ (3) mm P TDN Rang bupc vd dien ap nut: U TDN-min >P TDN vdi AP^ II tdn that cdng s u i t cua nhanh dudng day thu i; n la sd nhanh dudng day TDN-max n i y lai vi pham c i c yeu c l u vd phat tieu chuan phat ndng cua m i y phat cung nhu cac qua trinh can b i n g nang lUdng, cu the khi: P