Bi 2: Bo co Th Nghim iu Khin T ng

Sinh Vin Thc Hin: (Nhm 1 Sng th t) Nguyn nh Dng 09090421 Hunh Gia An - 09206461 Cao Trng Duy Dng - 09216381 : Kho st t tnh ng hc ca cc i tng sau: + H iu khin nhit . + H con lc ngc quay. Bi 1: Kho st t tnh ng hc ca h iu khin nhit dng iu khin ONOFF v PID. 1/ Kho st h h, nhn dng h thng theo m hnh Ziegler Nichols Gi s hm truyn m hnh l nhit c dng nh sau( trch ly t bi ging)

M hnh nh sau:

T ca s chnh phn mm Matlab nhn nt Start => SIMULINK => Simulink Library Browser thit k h thng.

Thng s khi step ci t nh sau: Chnh gi tr ca hm nc bng 1 cng sut cung cp cho l l 100% (Step time = 0, Initial time =0, Final time =1) Chnh thi gian m phng stop time = 2000s. Nhp cc thng s ca cc khi transfer funtion nh trn hnh v. Sau nhn nt Start Simunlink trn thanh cng c. Double click vo khi Scope s cho p ng t ca s Scope(Lu bn cn chn thi gian stop time)

Click vo biu tng Parameters, chn tab Data history v thc hin nh ci t sau, nhn Apply, OK:

T ca s Command windown. Hy thc hin th tc sau: >> plot(ScopeData.time, ScopeData.signals.values) >> grid on Sau y l cc xc nh thng s ca h h:

Ta nhn c L=75, T=1200 so vi ca h thng tuyn tnh ha l L=64, T=1495 2/ Kho st m hnh iu khin nhit dng phng php iu khin ON-OFF: T ca s son tho v h thng kn nh sau

Trong : + Tn hiu t vo hm nc u(t)=100. + Khi relay l b iu khin ON-OFF. + Gi tr li khi Gain l 200 Chnh thi gian stop times l 10 000(s) Nhn nt Start Simunlink tin hnh m phng: a/ u tin ta kho st vi vng tr 1/-1 cho khi Relay:

Vng tr 2/-2: (Stop times 40000)

Vng tr 5/-5: (Stop times 15000)

Vng tr l: 10/-10 (Stop times 40000)

b/ Tng kt thng s: Vng Tr 1/-1 2/-2 Delta- e1 1 2 (-)Delta-e2 3 4.4 Chu k ng ngt T 1161 1754

5/-5 10/-10

3.9 N/A

7.7 N/A

4101 N/A

Ta thy rng: khi vng tr cng ln th sai s ng ra cng tng v chu k ng ngt cng tng. Do vng tr ca khu Relay lm cho h thng p ng chm hn vi s thay i ca tn hiu sai s. Tc l vng tr cng ln th p ng ca khu Relay cng chm. c/Vi ring vng tr 2/-2 chng ta c cc gi tr biu din trn th:

d/ Nhn xt: Ta nhn thy rng nu cng gim rng vng tr th sai s cng nh(tin v 0). ng thi chu k ng ngt rt nh(v tin v 0). Trong thc t khng th thc hin b iu khin ON-OFF nh vy c , chng ta c th s dng gi tr sao cho dung ho gia sai s ng ra v chu k ng ngt.

2/Kho st m hnh iu khin nhit dng iu khin PID: (lu do thng s ca h thng qu ln nn vic tnh ton s gp kh khn nn chng ta s chn hm truyn tng ng vi h thng trn) T phn 1 ta xc nh c Cc1 thng s sau: L=50;T=500 Nn chng ta d dng c c thng s ca b iu khin PID nh sau:

Chnh Stop times l 1500. Nhp cc thng s PID, khu bo ho Saturation c gii hn upper limit = 1, lower limit = 0 (Ngha l ng ra b iu khin c cng sut cung cp t 0% n 100%). Ta c p ng sau:

Nhn xt: ta thy h thng p ng nhanh, kp thi hn Phng php iu khin ON-OFF th tn hiu ra lun dao ng quanh gi tr t. Phng php PID cho cht lng tt hn phng php ON-OFF

Bi 2: Kho st t tnh ng hc ca con lc ngc dng iu khin PID.

Ta c hm truyn ng vi con lc ngc nh sau:

Vi q= (M + m)(l+ m. l2) (ml)2 Cc gi tr c nh ngha v gi tr ca chng nh sau: M m b L cm I R tM KM KF F Khi lng xe ti con lc ............................. 900 gm Khi lng con lc ........................................ 100 gm Lc ma st ca trc........................................ 0.000 N/m/sec Chiu di tnh t trng tm con lc ti u trn 23.5

Moment ca lc qun tnh(Pendulum) .......... 5.3 gm-m2 bn knh dai truyn ........................................ .3 cm Thi gian p ng ......................................... 0.5 second tng tc trn 1 Volt in th .................... 17 rad/sec/V Khch i hi tip ........................................ 9/p V/rad/sec Lc tc dng

Cng thc trn c th vit li nh sau khi lc ma st bng 0

Trong :

Th s vo ta c hm truyn m hnh con lc ngc nh sau:

a/ Tnh ton h thng bng cng c SISO DESIGN TOOL(Bi tnh ton tham kho ti liu km theo) T ca s command windown: >> G=tf([0.04 0],conv([0.5 1],[0.0446 0 -1]))

Transfer function: 0.04 s ----------------------------------0.0223 s^3 + 0.0446 s^2 - 0.5 s - 1

>> H=tf(1,1)

Transfer function:

1 >> sisotool (G,1,H,1)

Yu cu ca h thng l: +Thi gian xc lp < 0.5s + vt l