NGHIEN CUU - TRAO DOI
N G H I E N C U V T H I E T K E , L A P R A P T R A M Q U A N T R A C , C A N H R A O P H O N G X A T U D O N G C O N H O
(*)TS. L l f U T A M B A T ThS. V U L E H A
KS P H A N H O N G M I N H
M O D A U
Cac he thong quan trie, phat hien va canh bao phong xa da ctiipc cac nUdc tren the gidi quan tarn nghien cdu, dng dung t d rat sdm. Theo thai gian va sU phat trien cua khoa hoc cong nghe, cac he thong quan trac, canh bao phong xa ngay cang hoan thien, vdi muc dich tao dupe cac trang bi do dac va truyen thong tin cay giua cac tram va trung tarn, qua do se danh gia va bao dong cac mdc do nhiem xa mot each tin cay nhat.
6 nUdc ta, quan trac phong xa bang mot so phuong phap khac nhau cung da dupe thuc hien tCf cuoi nhung nam 60 cua the ky trudc [1]. Khoang 15 nam t r d lai day, mot so tram quan trac da thuc hien viec quan trac bang thiet bi t u dong ghi nhan va canh bao phong xa. Cac ket qua quan trac tren thiet bi loai nay da co tac dung tot cho viec theo doi tinh trang phong xa d nhQng noi dat tram. Tuy nhien, no con nhupc diem la cac loi ky thuat khong dupe kiem soat, khong dupe loai trd, dan den xac suat bao dong nham co the xay ra.
Bai bao nay trinh bay mot ket qua nghien cdu cua de tai KC.05.15/06-10: "Nghien cdu, thiet ke, lap rap tram quan trac, canh bao phong xa ki'ch thudc nho, hoat dong lien tuc, tU dong truyen so lieu va phat tin hieu canh bao phong xa vdi dp tin cay cao nhd mot phan mem phan tich tinh trang tin hieu t d cac dau do
phong xa theo phuong phap trung phung".
E T H I E T K E T O N G T H E H E T H O N G Q U A N T R A C , C A N H B A O P H O N G X A (c»»
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Tram thu phong xa
Tram thu phong xa
Hinh 1: Tong quan he thong quan trac. canh bao phong xa (*) Vien Khoa hoc va Cong nghe Quin su
TAP CHI CQ KHI VIET NAM V So 12-Thing 12 nam2010
NGHIEN CUU • TRAO o 6 i Tren hinh 1 ta thay, he thong quan trac. canh bao phong xa co cac tram thu phong xa. moi tram thu nay gom it nhat hai dau do phong xa. tin hieu phong xa thu dupe tir hai dau do (sensors) sau khi duoc danh gia do tin cay se truyen ve Trung tarn dieu hanh. so lieu quan trac. cac mire do canh bao khac nhau cho ngudi su dung.
Viec truyen so lieu co the thuc hien bang cac bp thu phat vo tuy en tren tan so song cue ngan; truyen bang cap quang hoac qua internet.
EL THIET KE, LAP RAP TRAM TIT" DONG QUAN TRAC VA CANH BAO PHONG XA CB-MINI Tram duoc thiet ke vdi cac khoi chinh sau day :
II.1. Dau do phong xa
Dau do phong xa gom co hai ong dem (hoac hai gian ong dem) do hue xa gamma, beta hoac ca alpha (a), beta
(P), gamma (y). Hai ong dem duoc thiet ke tao thanh hai kenh do phong xa neng biet. dua ra tin hieu chuan TTL.
Tuy theo do nhay can lira chon de su dung mot cac dem kich thudc nho. ong dem kich thudc Ion hay ghep noi cac ong dem thanh gian ong dem de co cac dau do kich thudc ldn [2.3].
Tram quan trac, canh bao phong xa co nho-CB-MINI su dung hai dau do kich thudc Ion la cac ong dem Geiger-Muller.
Phong phong xa duoc xac dinh cho moi dau do II.2. Khoi dieu khien thu va truyen so lieu
Khoi vi dieu khien se thu cac xung phong xa tir hai kenh cua hai dau do. Tu do can cu vao so luong xung trong
mot don vi thdi gian cua moi kenh de danh gia va dua ra cac muc do canh bao khac nhau. Toan bo cac thong so do va canh bao se dupe truy en qua he thong \ d tuy en ve Trung tarn thu thap so lieu.
Thong tin canh bao 12V 5V J U L
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dieu khien trung tarn
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C = > | VHP 900 MHZ
Sensor 1 Sensor 2
I linh 2: Scr do tong quat tram thu va truyen so lieu phong xa
Khoi dieu khien duoc thiet ke tren nen tang chip vi dieu khien hieu nang cao. dien ap thap AVR cua hang
Atmel. Toe do 16 MIPS (tneu lenh/s). mat do tich hop cao. co nhieu tinh nang cao cap. tiet kiem nguon. cung cap mot giai phap dieu khien tot. So do khoi chuc nang cua mach vi dieu khien dupe trinh bav tren hinh 3
VHT 900Mhz EEprom SPI/JTAG configuration
Mega 8 8Kbytes
Flash Memory Program
High Performance
chipset H
Crytal lJ>Mhz r r
Sensor 1 Sensor 2
Power supply
1 linh 4 So do khoi chuc nang cua mach vi dieu khien
<3r TAP CHI CO KHI VIET NAM V So 12-Thana 12 nam 2010
NGHIEN CUU - TRAO DOI
Mach dien tu dieu khien chinh su dung chip A Y R AtmegaS. giao dien truven thona RS232; bp nha eeprom AT24C128 (16Kbytes). Dung luong bo nho lap tnnh 8KbyTes. giao dien lap trinh he thong SPI va JTAG. dieu khien vao ra (I 0 ) . dien ap lam viec tu 3.3V den 5.5V. So do nguyen ly mach dieu khien nhu hinh 4.
Bo vi dieu khien Trung t i m co hai cong thu xung tu hai sensors, cong RS232 ghep noi hai chieu voi Modem YHF Ngoai ra mach dieu khien con co giao dien 2 day (I2C). cic 1 0 . .. Cac trang thai lam v iec cung nhu so lieu luon dupe cap nhat ve Trung t i m
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Hinh 4 So do nguyen ly khoi dieu khien YHF 900 Mhz: Thiet bi truyen so lieu song cue ngan toe do toi da len den 115.200 kb s.
Eeprom: Bo nho luu tru du lieu, thiet ke su dung cac ho IC eeprom 24Cxx dung giao dien hai day (I2C). hoac ho 25CXX dung chuin SPI toe do cao.
Cac sensor 1 \ a 2 thu cac phong xa anfa. beta va gama.
SPI JTAG configuration: Giao dien lap tnnh. Cac phin mem dieu khien duoc lap tnnh tren ngon ngu l i p tnnh bang C C— va Assembly, qua giao dien nay duoc nap vao bo nho chuong tnnh cua chip v i dieu khien.
Cry tal 12Mhz: Clock he thong.
Chuc nang cua t r a m C B - M I N I :
Quan trac. canh bao phong xa voi cac muc do tin cay cao tai dia diem dat tram. Phat tin hieu bao dong voi do tin cay 3 cap.
Thiet bj dat tai C B - M I N I co kha nang trao doi thong tin hai chieu voi Trung t i m qua duong truy en thong
\ 6 tuyen Y H F 900Mhz. phin mem dupe noi mang tai Trung t i m se cap nhat va trao doi thong tin hai chieu cung phuong phap nhu vay.
Mot phuong an su dung truyen thong RS232 485 qua day cap huu tuyen cung duoc tinh den trong cac truong hop cac Tram thu phong xa dat qua each biet voi Trung t i m de dam bao thong tin hai chieu thuc su tin cay trong moi tinh huong
Modem \ 6 tuyen song cue ngan Y H F 900Mhz MaxStream:
Modem RF cung cap mot giai phap truyen so lieu tren giai tan so 900 M H z tin cay va chinh xac voi do chong
nhieu cao. Modem truy en so lieu qua chuan giao dien noi tiep khong dong bo RS232 RS485 RS422. ^=
2 4 TAP CHI CO' KHI VIET NAM *l* So 12 - Thing 12 nam 2010
NGHIEN CUU • TRAO DOI 11.3. Cau true phan mem va thuat toan dieu khien
Chuong tnnh phan mem nhung tren CB-MINI co
thiet ke mo. hoat dong dua tren tap tham so canh bao dupe cai dat truoc tu may tinh.
Eeprom: Cac ham doc va luu tru so lieu vao rom theo dia chi nhat drnh.
Thu phat VHF: Cac ham dieu khien thu va phat so lieu VHF.
Sensor 1. sensor 2: Cac ham thu va dem xung phat ra tu cac dau do.
I/O: Cac ham vao ra co ban cua chuong tnnh.
Cac modul phan mem. cac ham dieu khien duoc ghep noi vao chuong trinh chinh va dieu khien tuan tu theo cac so do thuat toan cu the.
L u u do thuat toan ciia chuffng t r i n h chinh:
Chuong trinh chinh lien tuc do va xac dinh cac muc do canh bao. sau khi lay mau xong truyen ve may tinh va xac dinh cac muc do canh bao. Hinh anh Tram tu dong quan trac va canh bao phong xa C B - M I N I duoc trinh bay tren hinh 5 va Luu do thuat toan dupe trinh bay tren hinh 6.
I linh 5: Tram tir dong quan trac va canh bao phong xa CB-MINI Phan mem dieu hanh hoat dong cua khoi vi dieu
khien dupe nap tir may tinh. trong truong hop thong thuong, muc bao dong dupe dat vdi so dem cua moi kenh Ion hon 3 lan phong tai v i tri dat.
Ca hai kenh deu vupt trong thai gian 5 giay se dua ra bao dong cap 1, den 15 giay se dua bao dong cap 2 va 20 giay se phat tin hieu bao dong cap 3. Cac truong hop mot dau do bi hong (mat tin hieu) hoac mot dau do bi phong dien (so xung rat Ion) hay chi mot dau do bj loi cho so dem cao hon 3 lan phong se thong bao "loi ky thuat"
Bit clan KLhcn tao cac tham so he thong Xap xep tham so vao 1
cac bien Cho phep thu va thay doi tham so Do vaxac dinh rrnrc do
canh bao mm: 1 Khong
Bao clong raurc 1 Do va xac dinh mire 2
Hinh 5: Luu do thuat toan chuong trinh chinh
TAP CHI CO KHI VIET NAM • So 12 - Thang 12 nam 2010
NGHIEN CUU - TRAO OOl
II.3. Trung tarn quan ly va t h u so lieu Trung tim quan ly va thu so lieu (goi tit la Trung
t i m ) co chuc nang thu thap va xu ly so lieu, la mot he thong may tinh duoc noi mang. cac may tinh nay duoc cai dat p h i n mem thu thap. xu ly. truyen so lieu vo tuyen (May thu. phan mem co kha nang phan tich trang that tin hieu tu hai dau do)- Cat dat cac muc canh bao va cac tham so hoat dong cho C B - M I N I .
Thu nghiem hoat dong cua tram quan trac va canh bao phong xa 0 cac cu ly khac nhau ve:
- Thu ket noi truyen so lieu \ 6 tuyen.
- Thu do cac muc do phong phong xa Nfv a Df
- Thu do voi cac muc do phong xa 0 cac tinh huong khac nhau.
- Thu dieu kien canh bao hong sensor: ngat mot trong hai nguon sensor.
Ket qua thu thap du lieu duoc tnnh bay tren cac hinh 7. 8 va 9.
Tram tif eTpng qucin trSc ve c&nh bao ph6no, xa CO-MINI
-
I t * m
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1 linh ~ Giao dien quan sat tin hieu truyen ve tu train CB-MINI Tram tir C$ng quan Irfie va canh bao pMng xa CO-MINI
Hinh S Do muc phong. muc do duoc trung binh la N..= 15 va Df=8 Tram 61/ eTSng quan Irft-c va tinh bao ph6ne, xa Cft-MINI
Hinh ^ Dua nguon phong xa den gan cac dau do
Cac tham so ve cac muc so xung canh bao cung nhu so xung phong nen co the duoc thay doi va cap nhit den tung tram quan trie tir phan mem trung t i m thong qua cic hop van ban va nut lenh truy en so lieu.
Cac tham so luu tru trong bo nho R O M o tram quan trie cung co the duoc doc ve va hien thi tren giao dien phan mem.
N h u vay. so lieu phong phong xa cua moi kenh se phai dupe xac dinh tai nhung diem dat tram quan trac.
muc bao dong co the thay doi va nap vao khoi dieu khien tu may tinh.
He thong hoat dong doc lap bang accqui. dien lubi.
dien ap 12Y. tieu thu nang lupng thap. trung binh tir 4-6W.
KET LUAN:
Tram quan trac. canh bao phong xa tu dong kich thuoc nho co the dupe coi la tram quan trac. canh bao phong xa the he m o i : ngoii kha nang tu dong ghi nhan va luu tru so lieu, tram con co kha n i n g p h i n tich tinh trang tin hieu phong xa va phat tin hieu bao dong voi do tin cay cao hon han so v o i cic tram quan trac su dung ky thuat thong thuong nhu truoc day.
Tram co the co ket cau gon. nhe hon khi thuc hien cac quan trac. canh bao phong xa moi truong.
Tram co the ung dung de quan trac. canh bao phong xa tu dong o cac vi t n c i n kiem soat phong xa chat che nhu cac cua khau. cac duong van chuyen co nguy co cao ve van chuy en phong xa.
D61 vai cac cong trinh trong diem can duoc trang bi tram quan t r i e , canh bao phong xa loai nay vai kich thuoc cac dau do phong xa khac nhau theo yeu cau do nhay.
T a i lieu t h a m k h a o :
1 Luu Tarn Bat va cac CTY: Nghien cuu xac dinh muc do nhiem ban phong xa cua khong khi 0 cac TYung tain cong nghiep dong din cu va de suat bien phap phong tranh. Bao cao khoa hoc tong ket de tai cap Mia nuoc 5202-06-01. 1981-
1985. Ha Noi 2-1986.
2 Lmi Tarn Bat. Khong Nam Khang: Nghien cuu. lap rap gian ong dem de ning cao dp nliay cho thiet bi tir dong ghi nhan phat Men va canh bao phong xa. Ky yeu Hoi nghi khoa hoc Cong nghe Co kin che tao toan quoc lan thu 2.
NXB KHKT. Ha Noi 2010.
3. Thiet ke. lap rap bo dau do phong xa dai rong. Tap chi Co khi Yiet Nam so 11. 11-2010.
2 6 TAP CHI CO' KHI VIET NAM «V» S6 12-Thang 12 nam 2010
