ứng dụng mạng nơron trong chuẩn đoán trạng thái kỹ thuật động cơ diesel tàu thuỷ

I KHOA HQC - CONG NGHJ

UfNG DUNG MANG NOlRON TRONG CHUAN OOAN

TRANG THAI KY THUAT BONG COf DIESEL TA U THUY

Tdm tUt: Chuin aoin ky thu$t, atf bio stf d

phtfc vtf cho viic Idem tra, khai thic an toin dc h$

thing agng Itfc tiu thup Ii nhiim vg hit stfc quan

trgng. Viic xiy dtfng dc mo hinh dinh gii, chin

ddn vi dtfbio "thing minh " hdn Ii phd hgp vdi xu

thi Chung cua kythu$tSuf dung m9ng neuralnhin

(90 dixiy dtfng dc mi hinh nhin d^ng vi chuin

ddn ky thu$t Oang autfc Ung dung nhuli giil phip

tin dV'

Bii vlit xiy dtfng mi hinh m^ng neural p/igc vy

cho ainh gii trgrtg thii vi chin Odn stfdaing cd

aiesel tiu thdy. Diy Ii mi hinh mdi cd thi dip Ung

augc tOiQng vin Oi thtfc tiin xay ra trong qd trinh

v$n hinh, do tii, sCra chffa tren dc tiu thuy dng

suit Idn, d hinh Mnh dng tic Oil ngiy trin biin,

gip phin aim bio stf ho0t Oing an toin, tin dy

ctia hi aing Itfc tiu thuy.

Abstract: Technical diagnosis and problems

forecast In ship dynamics system Inspection

and sate operation Is very neccesray. The develop￾ment of evaluation model and more "Intelligent"

diagnosis Is consistent with general techniques.

Using artificial neural networks to set up the

Identification model and diagnostic techniques are

being applied as a rellabte solution.

This article has developed neural network model

tor state assessment and marine diesei engines

diagnostic. This model can apply for practical

proltlwns occur during operation, maintenance and

repair on large-capacity ships which have long

fourrteys at sea, ensuring operatlortal safety and

r^lablllty of ttte ship dynamics system.

1. Bii toin dinh gi i trgng thi i

Cdng tic dinh gii trgng thii thgc cua mdt hO

thdng trong dldu khidn ti rit cin thidt, gidp cho qui

trinh khai thic, vin hanh va didu khidn hd ttidng dupc

tdi Uu. MOt hO thdng didu khidn cd qui trinh dinh gii

trgng thii cda cic sd tlOu dua vio se giup giim thilu

ding kd sal sdt trong qui trinh didu khiln. tim cho

ehdt lupng tdng thd cda hd thdng didu khidn ning tdn.

Cd nhidu phuong phip dinh gid trgng thai, trong

bii vidt niy chung tdl sd dgng phuong phip binh

phuong cgc tidu (least squares).Ndi dung cOa phUOng

phip niy ti do cic tfn hl$u vio dd danh gii cic tfn

hi$u bj mdt (chua bidt) ho$c sal sd cao d l cho ra mdt

bd tfn hlOu dldu khidn phd hop nhit (best fit).

Gpi Z =[z-|, zg, -, ZnV ti mdt vector chda n tfn hidu

do cda mdt h i thdng, Z j ti cic gii trj dung (nhUng

chua doge bidt). Trong cic hd thdng vit ly chung ta

ludn bidu didn Z j theo vector chUa eic ngudn kleh

thfeh X dd tgo ra tfn hlOu Z thdng qua mdt ma tr$n lien

kdtH nhu sau:

TS. OONG VAN HUdNG

Trtfdng D9I hgc GTVT TP. Hi Chi Minh

Trong dd: Z j la vector cdp n, X Ii vector cdp m U

ma tran H cd kfch thudc la nxm. Ndu gpi E la vector

chda cic gia tri sai sd, khi dd ta ed the vidt:

Z = ZT+ E (2)

Khidd: E = Z-Z T = Z-H*X (3)

Thdng thudng gii trj chlnh xac cda ngudn kk^

thfch X khdng thd xac djnh dupe mi chung ta cd th^

danh gii dUpe (gii trj danh gii ta gpi la X); tde niy

gii trj sal s6 dupe dinh gii E se ti :

E=z-H- X (4)

H* X dupe gpi ti ^ p gia trj danh gii cda tip tfn

hlOu Z. Khi dd chung ta cd ttid vIet:

E=Z-Z=Z-H' X =E-H * i^ -X) (5)

Chung ta cd thd xac djnh gii trj dinh gii X ttieo

cic ChT tidu dinh gi i E va Z ddng phUdng phip

binh phUdng epe tilu thdng qua him f dupe djnti

nghTa ti:

1=1

Trong dd e, ta ci c gi i trj sai sd Ung vdi tfn hlOu thd

i. D l ting kh i nang danh gi i chiing ta cd thd difa

thim vi o cac gi i trj trpng sd Wj. Khi dd hi m myc tiiu

cda phUPng phap cgc til u binh phuong sal sd xic

dinh bdi:

NhlOm vy cda bi i toin tidp theo t i chung ta dl tlm

g i i tri nhd nhit cda hi m f duoc cho bdi cdng thdc (7)

theo ci c bidn '^i . Dldu kiOn dd hi m f dgt cgc tilu Ii:

df I = 0 /m

dX|j <8)

Hay:

f,

'

r

[

w,e,

ft￾ax,

*, d Xj

a-.,

<*>.

C j 3e,

ax,*"

ac.

ax, •

*.-. "ix.

.+ w •°-a^

*. • "ax.

ae

• "ax

ZT = H*X (1)

(9)

Luu y riing ky hi$u I ' ndi li n ring phUdng trinh

(9) dU9c dinh gi i tCI ci c trang thi i din h gi i X ^ theo

c i c gi i trj tr^ng ttii i tlii;c chUa bilt. ChOng ta thay thi