Ứng dụng mạng nơ ron - mờ để điều khiển SVC giữ điện áp tại nút có phụ tải thay đổi

Hdi nghi Khoa hgc ky niem 35 ndm Viin Khoa hgc vd Cdng nghi Viet Nam - Hd Ndi 10/2010<br /> <br /> <br /> U*NG DUNG MANG NO RON - MOf DE DIEU KHIEN SVC<br /> GIIT DIEN AP TAI NUT CO PHU TAI THAY DOI<br /> Nguyen Thanh Quang<br /> Vien Khoa hoc nang lugng<br /> Nha A9, sd 18 - Hoang Qudc Viet, Ciu Giiy, Ha Ndi<br /> Email: ntquang.dlna@gmail.com<br /> Tom tat:<br /> Diin dp Id mdt trong nhiing thdng sd dnh huong din chdt lugng dien ndng.<br /> Viec sit dung thiit bi bit ngang SVC di ddm bdo gid tri diin dp dd dugc khdng<br /> dinh. Tuy nhiin chdt lugng diiu chinh cua thiit bi bit phu thudc nhiiu vdo bd diiu<br /> khiin SVC. Bdi viit xin gidi thiiu vi khd ndng sit dung bd diiu khiin trin ca sd<br /> mgng naron - md di diiu khien SVC nhdm muc dich gid diin dp nut tdi vd kit qud<br /> tinh todn ieng dung trin mot ludi diin cu thi.<br /> Abstract:<br /> Voltage is one of the parameters affecting power quality. The use of SVC<br /> equipment to ensure the voltage value has been confirmed. However the quality of<br /> the equipment to adjust compensation depends on SVC controller. Posts introduce<br /> the possibility of using the controller based on neural networks -fuzzy control to<br /> keep aimed SVC voltage load bus and the results calculated on a grid application<br /> specific<br /> 1. BAI TOAN DIEU CHINH DIEN AP TAI NUT TAI CUA THIET BI [3]<br /> Kha nang dieu chinh dien ap cua thiet bi bii dugc xet thdng qua he thdng cung cap dien<br /> dugc bieu dien bang mach tuong duong Thevenin mgt pha d hinh 1 dudi day:<br /> E<br /> <br /> <br /> AUx=jIs.Xs<br /> <br /> IT -is<br /> AUR = Rs.Is<br /> <br /> U<br /> b)<br /> <br /> <br /> <br /> <br /> YT=GT+JBT<br /> <br /> <br /> <br /> <br /> a)<br /> <br /> <br /> <br /> Hinh 1: a) mgch tuang duang; b) dd thi vec ta luc chua bit; c) dd thi vie to luc cd bii<br /> <br /> <br /> 357<br /> Tiiu ban: Mdi tru&ng vd Ndng lugng ISBN: 978-604-913-013-7<br /> <br /> <br /> Khi khdng cd thiet bi bu, tir hinh a viet dugc phuong trinh:<br /> <br /> AU = ( R , + j X , ) ^ ^ ~ J Q ^ = ^ ^ ^ ^ + ^ ^ - Q ^ + j ^ ^ ^ ^ ~ ^ ^ Q ^ (1)<br /> ^ ^ u u u<br /> hay:AU = AUR+jAUx(2)<br /> Khi cd thiet bi bu, tien hanh dieu chinh cdng suit phan khang thiit bi bu dl cd: IU 1=1 E I.<br /> hay: I E P=| U-f ^^^^ ^^^"^^ ? +1 ^SPT "RsQs a .3.<br /> U U<br /> vdi Qs = QT + Qc, Trong dd: Pj - cdng suat tac dung ciia phu tai; Qj - cdng suit phan<br /> khang cua phu tai; Qc - cdng suat phat ra ciia thiit bi bii.<br /> Dat a = R s V Xs^ b = 2U^Xs, c = (U^ + RSPT)^ + (XSPT)^ - E^U^<br /> <br /> _ -b±Vb'-4ac ^^^<br /> suy ra: Q^ = (4)<br /> 2a<br /> Nhu vay vdi mdt gia tri Pj bat ki cua phu tai ludn tim dugc Qs, vay ludn tim dugc gia tri<br /> Qc cin thiit dk giii dien ap mit phu tai khi cdng suit phu tai thay ddi, nlu thiit bi bii cd pham<br /> vi dieu chinh dii rgng.<br /> <br /> <br /> 2. KHA NANG DIEU CHINH DIEN AP CUA BO SVC<br /> ciu tao chung cua thiit bi bii ngang tinh SVC [6] diu tir hai loai phin tir co ban sau:<br /> - TCR: Thyristor controller reactor (cudn khang dugc dilu khiln bing Thyristor)<br /> - TSC: Thyristor switched capacitor (tu ddng cit bing thyristor)<br /> Dac tinh dieu chinh cua SVC xay dung dugc dua vao nguyen ly lam viec cua thyristor. Xet<br /> thanh phin TCR.<br /> <br /> Dien khang cua TCR: X^ = '^'""'" (5)<br /> (Pi(ao)<br /> <br /> Khi ao thay ddi lien tuc tir 7i/2 din n thi Xk thay doi lien tuc tir Xk^in din 00.<br /> Trong thuc tl do SVC ciu tao td hgp TCR vdi TSR va TSC nen Xk thay ddi cdng suit tieu<br /> U'<br /> thu Qk tren SVC ciing thay ddi theo vi: Q^ = — . Neu SVC cd tri sd dien khang thay ddi huu<br /> <br /> ban tir Xkmin din Xkmax thi cdng suit tieu thu thay ddi tir Qkmax din Qkmin-<br /> Nhu vay, khi bd SVC dugc lip dat tai mit cin dilu chinh dien ap thi viec dilu khiln dl giu<br /> dien ap tai thanh cai U khdng ddi khi phu tai thay ddi lien tuc la hoan toan thuc hien dugc nhd<br /> viec thay ddi gdc md a cho bg TCR.<br /> <br /> <br /> 3. inVG DUNG MANG NO RON - MCJ TRONG DIEU KHIEN SVC G l f DIEN AP<br /> NUT KHI PHU TAI THAY DOI<br /> Da cd mdt sd nghien ciiu sir dung mang no ron md trong dilu khiln SVC [7-8] tren ludi<br /> dien nhung chu ylu nang vl phuong phap luan va hgc thuat, chua di vao sd lieu ung dung cu<br /> <br /> 358<br />  Hdi nghi Khoa hgc ky niem 35 ndm Viin Khoa hgc vd Cdng nghi Viet Nam - Hd Ndi 10/2010<br /> <br /> the, cdn mdt sd sai sdt va kha nang ling dung cdn ban che. Trong nghien ciiu nay, chiing toi<br /> gidi thieu phuong phap ling dung bd cdng cu sir dung mang no ron md ANFIS [10-12], trong<br /> dieu khien SVC giir dien ap tai niit cd phu tai thay ddi va ket qua tinh toan cua mo binh tren<br /> mot ludi dien tham chieu.<br /> Trong bai toan dieu khien SVC nay, bien dau vao la cong suat tac dung (PT) va cdng suit<br /> phan khang (QT) cua phu tai, bien dau ra la gdc md alpha (a) ciia thyristor trong bo TCR.<br /> Bd dieu khien sir dung mang noron - md dugc sir dung trong trudng hgp thiit kl bo dilu<br /> khien kinh dien gap khd khan khi phai giai quyet bai toan cd do phiic tap cao, do phi tuyin<br /> ldn, sir thay ddi thudng xuyen trang thai va cau tnic doi tugng. Trong trudng hgp giai quyet<br /> bai toan dieu chinh dien ap neu tren, cac mdi quan he d phuong trinh (3); (4) va (5) la mdi<br /> quan he phi tuyen do dd ap dung bd dieu khien no ron - md la rat phii hgp do khai thac dugc<br /> uu diem ndi trgi ciia Id gie md va mang no ron nhan tao la kha nang giai quyet cac bai toan<br /> phi tuyen, kha nang hgc va cap nhan thdng tin mdi [2-3].<br /> Y tudng CO ban cua bg dieu khien noron - md nhu sau: Sir dung md hinh no ron nhan tao,<br /> thdng qua mdt giai thuat hgc thich hgp de he thdng md hgc cac thdng tin vao - ra cho trudc, tir<br /> do xay dung dugc mdt he thdng md cd the suy luan cac dap ling dau ra chinh xac hon tir cac<br /> kich thich dau vao dua tren cac tham sd ciia mang da dugc hgc.<br /> Hinh 2 la cau tnic md binb ciia mot mang no ron - md don gian trong phan mem<br /> MATLAB (ggi la ANFIS) vdi hai dau vao va mot dau ra.<br /> <br /> <br /> <br /> <br /> Hinh 2: Cdu true mdt mgng noron md cua bdi todn diiu khiin SVC<br /> Vdi cau tnic nhu vay he thdng nay boat ddng nhu mdt mang no ron that su. Cac cdng thiic<br /> xac dinh gia tri tai moi mit cua mang deu sir dung cac phep toan trong Id gie md de suy luan<br /> hay tinh toan.<br /> Su dung bd cdng cu ANFIS trong phdn mim MATLAB tinh todn kiim tra tren mot ludi diin<br /> 3 pha cu thi<br /> Xet ludi dien 1 lOkV tuyin Hung Ddng - Dd Luong (tinh Nghe An) cd so dd nguyen ly<br /> nhu trong hinh 3.<br /> <br /> <br /> <br /> <br /> 359<br /> Tiiu ban: Mdi tru&ng vd Ndng lugng ISBN: 978-604-913-013-7<br /> <br /> <br /> Hung Ddng (Bi) Dd Luong (B2)<br /> ( HTD \ • PT ' JQi<br /> AC-185<br /> E=110kV L = 48km U<br /> o VC: Qcmax 94,88 MVAr<br /> <br /> Hinh 3: So dd nguyen ly luoi diin llOkVHung Ddng - Dd Luong (tinh Nghi An)<br /> Trong so dd hinh 5, phu tai tai dilm dat SVC (Dd Luong) cd PT biin thien tir 0 - 60 MW,<br /> QT tir 0 - 60 MVAr, Qcmax = 94,88 MVAr. Diing bd dilu khiln noron - md dieu khiln SVC<br /> giir dien ap tai diem dat tu.<br /> De cd the thiet ke bd dieu khien, tien hanh md phdng so do tren SIMULINK [1] [5] trong<br /> phan mem MATLAB de lay mau tin hieu. Bd mau tin hieu bao gdm thdng sd phu tai PT va QT<br /> va tin hieu dau ra la gdc dieu khien a. Sau khi cd dugc bd mau, tien hanh huan luyen tren<br /> mang no ron - md de tim ra bd dieu khien md thich hgp.<br /> <br /> % 'W^ %<br /> :E^<br /> <br /> (^ ^ ^ N,„.„<br /> <br /> <br /> H^ ounhbZ<br /> <br /> <br /> <br /> <br /> : &<br /> <br /> Pt<br /> <br /> <br /> <br /> <br /> &<br /> ^m.<br /> FTinh 4: Md hinh ludi diin 3 pha cd SVC vdi hd diiu khiin hdng mgng no ron - ma<br /> Vdi bd dieu khien md da dugc huan luyen thi mdi gia tri cua phu tai se cho ra mdt gia tri<br /> gdc thich hgp, de dien ap thanh cai dugc giii nguyen. Hinh 5 la dd thi thi hien gia tri ciia dien<br /> ap mit dat tu bii tuong ling mdt gia tri phu tai (khac vdi cac cdng trinh cdng bd trudc dd [8]:<br /> dd thi la do thi lien tuc), cho thay dien ap ludn dugc giii gin vdi gia tri mong mudn.<br /> <br /> 112<br /> 110<br /> 108 • 11<br /> 106 •<br /> > 104 • • -• '^ _ : g, H<br /> 5 102 • " . H M ; • • •<br /> 100 •B • • JI<br /> 9i %<br /> 98<br /> 96 •.<br /> — f — 1 — 1 — t — 1 — 1 — » — 1 — 1 — * — I — 1 — 1 — 1 — 1 — 1 — ( — ( — 1 — 1 — 1 — , — 1 1<br /> <br /> tai (P,0)<br /> <br /> <br /> •CoSVC "KhongcoSVC<br /> <br /> <br /> Kinh 5: Diin dp cua niit khi cd vd khdng cd SVC ung vol mdi mdt gid tri tdi<br /> <br /> 360<br />  Hdi nghi Khoa hgc ky niem 35 ndm Vien Khoa hgc vd Cdng nghi Viet Nam - Hd Ndi 10/2010<br /> <br /> <br /> 4. KET LUAN<br /> Ket qua phan tich va tinh toan thir nghiem tren day cho thay, cd the ling dung mang no ron<br /> md de dieu khien SVC vdi muc dich giir dien ap vdi nhirng uu dilm sau:<br /> - Cau tnic bd dieu khien don gian, tan dung tinh dap ling nhanh ciia bd dieu khien md,<br /> tinh chinh xac cua bd dieu khiln no ron<br /> - Cd kha nang cap nhat va hgc hdi thdng tin mdi nhu mang no ron.<br /> - Giai quyet tinh phi tuyen cua bai toan.<br /> - Cd the ap dung bd dieu khien cho diem tai bat ky neu biet dung lugng tu bu va dai bien<br /> thien cua tai.<br /> Nghien ciiu tiep theo chiing tdi se tap tmng giai quyet mdt sd van de sau:<br /> - Tinh kinh te ciia bd dieu khien.<br /> - Pbu tai cd sir gia tang theo thdi gian va khi vugt ra ngoai pham vi dieu chinh bg dieu<br /> khien mat tac dung. Tuy nhien, dieu nay cd the khac phuc dugc neu ta du bao trudc<br /> dugc sir gia tang phu tai.<br /> - Thuc te khdng chi pbu tai ma cdn nhieu thdng sd anh hudng den dien ap, do do can<br /> nghien cihi bd sung nhiing bien dau vao vdi do phiic tap cao hon.<br /> - Xem xet anh hudng ciia cac sdng hai bac cao tdi chat lugng bd dieu khien no ron - md.<br /> - Nghien ciiu uu the sir dung mang no ron md trong bd dieu khien SVC ve tdc do dieu<br /> khien, kha nang dap ling cac bien ddng ldn, nhat la bien ddng ve ngudn phat.<br /> <br /> <br /> TAI LIEU THAM KHAO<br /> 1. Trin Bach, 2002, "Ludi diin & hi thdng diin tap 2 ", NXB KHKT.<br /> 2. Bill Cdng Cudng, Chu Van Hy, Phan Xuan Minh, Nguyen Doan Phudc, Nguyen<br /> Hoang Phuong, 1998, "Hi md vd ieng dung", NXB KHKT.<br /> 3. Phan Dang Khai, Huynh Ba Minh, 2001, "Bii cdng sudt phdn khdng ludi cung cdp vd<br /> phdn phdi",^XBYAAKl.<br /> 4. Phan Xuan Minh, Nguyen Doan Phudc, 2002, "Ly thuyit diiu khiin md", NXB<br /> KHKT.<br /> 5. Nguyen Phung Quang, 2000, "Matlab & Simulink", NXB KHKT.<br /> 6. La Van Ut, 1996, "Cdc thiit bi bit tinh cd diiu khiin - iing dung trong hi thdng diin ",<br /> Trudng Dai hgc Bach Khoa Ha Ndi.<br /> 7. Nguyin Minh Tri, 2006, "Ifng dung mgng hi md diiu khien SVC trin ludi diin",<br /> Luan van cao hgc, Trudng Dai hgc Bach Khoa Da Nang.<br /> 8. Trin Dinh Tan, 2007, "Ifng dung mgng na ron md di diiu khiin tu bii tinh ", Luan van<br /> Cao hgc, Tmdng Dai hgc Bach Khoa Da Nang.<br /> 9. Ching Teng Lin and C.S.Georgle Lee, "Neural fuzzy systems ", Intemational Edition.<br /> 10. Heikki Koivo, Adaptive Neuro, 2000, "Fuzzy Inference Systems (ANFIS)", Website<br /> www.control.hut.fi.<br /> 11. Heikki Koivo, 2001, "Fuzzy exercises". Website www.control.hut.fi.<br /> 12. "Fuzzy Logic Toolbox for use with MATLAB, User's Guide Version 2", The Math Works,<br /> Inc.<br /> <br /> <br /> 361<br />