磁盤(pán)驅(qū)動(dòng)讀取系統(tǒng)的分析設(shè)計(jì)

...wd......wd......wd...磁盤(pán)驅(qū)動(dòng)讀取系統(tǒng)的分析設(shè)計(jì)一、閉環(huán)系統(tǒng)的性能分析〔1〕確定使閉環(huán)系統(tǒng)穩(wěn)定的Ka的取值范圍>>G1=tf([5000],[1,1000]);>>G2=tf([1],conv([1,0],[1,20]));>>G=series(G1,G2)Transferfunction:5000------------------------s^3+1020s^2+20000sg3=一一開(kāi)環(huán)傳函G3=一一閉環(huán)傳函>>symsKden>>den=[11020200005000*K];>>K=den(2)*den(3)/den(1)/5000K=4080有勞斯判據(jù)可得k的范圍是0<K<4080〔2〕在上述取值范圍內(nèi)取較小和較大的兩個(gè)Ka值，仿真閉環(huán)系統(tǒng)的階躍響應(yīng)，并進(jìn)展分析K=100時(shí)>>g=100*Gg1=feedback(g,1)C=dcgain(g1)Transferfunction:500000------------------------s^3+1020s^2+20000sTransferfunction:500000---------------------------------s^3+1020s^2+20000s+500000C=1[c,t]=step(g1);>>[y,k]=max(c);>>percentovershoot=100*(y-C)/Cpercentovershoot=21.6918調(diào)節(jié)時(shí)間函數(shù)調(diào)節(jié)時(shí)間函數(shù)>>t=setllingtime(g1)t=0.3697K=1000時(shí)>>g=1000*GTransferfunction:5e006--------------------------------s^3+1020s^2+20000s>>g2=feedback(g,1)Transferfunction:5e006------------------------------------------s^3+1020s^2+20000s+5e006>>[c,t]=step(g2);>>C=dcgain(g2)C=1>>[y,k]=max(c)y=1.7109k=11>>percentovershoot=100*(y-C)/Cpercentovershoot=71.0891t=setllingtime(g2)t=0.4989超調(diào)量調(diào)節(jié)時(shí)間0.3697(s)K=1000時(shí)超調(diào)量調(diào)節(jié)時(shí)間0.4989(s)〔3〕考察擾動(dòng)信號(hào)為單位階躍時(shí)，上述兩個(gè)Ka取值情況下，系統(tǒng)的抗干擾能力，并進(jìn)展分析>>g2=tf([1],conv([10],[120]))Transferfunction:1----------s^2+20s>>g1=tf([5000],[11000])Transferfunction:5000-----------s+1000>>symsk>>g3=feedback(g2,g1,1)Transferfunction:s+1000-------------------------------s^3+1020s^2+20000s-5000>>g3=feedback(g2,-g1,1)Transferfunction:s+1000-------------------------------s^3+1020s^2+20000s+5000>>g4=-g3Transferfunction:-s-1000-------------------------------s^3+1020s^2+20000s+5000--------------------擾動(dòng)輸入的傳遞函數(shù)當(dāng)K=100時(shí)>>g=tf([-1-1000],[1102020000500000])Transferfunction:-s-1000---------------------------------s^3+1020s^2+20000s+500000>>[c,t]=step(g);>>[y,k]=min(c)y=-0.0024k=15c〔t〕=2.4*10-3〔s〕當(dāng)K=1000時(shí)>>g=tf([-1-1000],[11020200005000000])Transferfunction:-s-1000--------------------------------s^3+1020s^2+20000s+5e006>>[c,t]=step(g);>>[y,k]=min(c)y=-3.4308e-004k=11c〔t〕=0.34*10-3〔s〕(4)針對(duì)如下的性能指標(biāo)要求，折中選取一個(gè)適宜的Ka值取Ka=100二、速度反響系統(tǒng)的性能分析〔1〕運(yùn)用第3章中所學(xué)的勞斯判據(jù)，確定要使閉環(huán)系統(tǒng)穩(wěn)定，Ka和K1應(yīng)如何選取Ka=100，K1=0.03〔2〕針對(duì)你選取的Ka和K1，仿真閉環(huán)系統(tǒng)的階躍響應(yīng)，并計(jì)算超調(diào)量、調(diào)節(jié)時(shí)間和對(duì)單位階躍擾動(dòng)的最大響應(yīng)值。>>g1=tf([5000],[11000])Transferfunction:5000--------s+1000>>g2=tf([1],[120])Transferfunction:1------s+20>>g3=tf([1],[120])Transferfunction:1------s+20>>g0=feedback(g3*feedback(100*g1*g2,0.03,-1),1)Transferfunction:500000--------------------------------------------s^3+1020s^2+35000s+500000>>t=setllingtime(g0)t=0.2300>>[c,t]=step(g0);>>C=dcgain(g0)C=1>>[y,k]=max(c)y=1.0206k=38>>percentovershoot=100*(y-C)/Cpercentovershoot=2.0650超調(diào)量調(diào)節(jié)時(shí)間0.2300(s)>>g10=-feedback(g2*g3,-g1*100*(0.03*1/g3+1),1)Transferfunction:-s-1000----------------------------------------------------------------擾動(dòng)輸入傳遞函數(shù)s^3+1020s^2+35000s+500000>>step(g10)>>[c,t]=step(g10);>>[y,k]=max(c)y=0k=1>>[y,k]=min(c)y=-0.0020k=38對(duì)單位階躍擾動(dòng)的最大響應(yīng)值：c〔t〕=2.0*10-3〔s〕。三、PD控制器的性能分析——根軌跡法利用根軌跡圖，分析K3的變化對(duì)系統(tǒng)性能指標(biāo)的影響，選取能夠滿足以下指標(biāo)要求的K3值>>G3=series(G,