用MATLAB画零极点图ppt课件

用MATLAB将传递函数化为零极点增益模型并绘制零极点图,1,将传递函数化为零极点增益模型并绘制零极点图,num=328;den=13842;G=tf(num,den)Transferfunction:3s2+2s+8-s4+3s3+8s2+4s+2G1=zpk(G);z=G1.z;p=G1.p;Z=z:;P=p:;k=G1.k;pzmap(G);pzmap(G1);gridon,2,将传递函数化为零极点增益模型并绘制零极点图,Transferfunction:3s2+2s+8-s4+3s3+8s2+4s+2将上式化为零极点增益模型，并绘制零极点图。,3,num=328;den=13842;G=tf(num,den),求传递函数。命令后无“;”则屏幕立即显示，否则不显示。,Transferfunction:3s2+2s+8-s4+3s3+8s2+4s+2,4,G1=zpk(G);%化为零极点增益形式z=G1.z;%将G1零点存入zp=G1.p;%将G1极点点存入pk=G1.k;%将G1增益存入k,Z=z:Z=-0.3333+1.5986i-0.3333-1.5986iP=p:P=-1.2496+2.2082i-1.2496-2.2082i-0.2504+0.4980i-0.2504-0.4980i,显示零点,显示极点,%下面语句也可获得零极点。z,p,k=tf2zp(num,den),5,pzmap(G1);%绘制零极点图gridon%打开绘图网络,鼠标指向某零点或极点会显示该方框。极点、阻尼比、超调量、固有频率wn.,6,7,化传递函数为零极点形式,num=121;den=15389;t=0.2;G2=tf(num,den,t)%有采样时间t，则显示为脉冲传递函数，自变量为z,Transferfunction:z2+2z+1-，Samplingtime:0.2z4+5z3+3z2+8z+9,Transferfunction:z2+2z+1-z4+5z3+3z2+8z+9Samplingtime:0.2,8,G22=zpk(G2)%求离散系统G2零极点,Zero/pole/gain:(z+1)2-(z+4.635)(z+1)(z2-0.6347z+1.942)Samplingtime:0.2,9,num=121;den=15389;t=0.2;G1=tf(num,den)%没有采样时间t，则显示为传递函数,自变量为s,Transferfunction:s2+2s+1-s4+5s3+3s2+8s+9,10,G11=zpk(G1)%求连续系统G1零极点,Zero/pole/gain:(s+1)2-(s+4.635)(s+1)(s2-0.6347s+1.942),11,num=121;den=15389;z,p,k=tf2zp(num,den)%化传递函数为零极点增益形式,z=-1-1p=-4.63470.3174+1.3569i0.3174-1.3569i-1.0000k=1,12,化零极点增益形式为传递函数,num1,den1=zp2tf(z,p,k)%化零极点增益形式为传递函数,num1=00121den1=1.00005.00003.00008.00009.0000,13,系统的串、并联的传递函数,2s2+6s+5G1=-s3+4s2+5s+2s2+7s+12G2=-s2+3s+2分别求G1、G2串、并联后的传递函数。,14,num2=1712;den2=132;G2=tf(num2,den2)；,num1=265;den1=1452;G1=tf(num1,den1)；,G=series(G1,G2)或G=G1*G2%串联,Transferfunction:2s4+20s3+71s2+107s+60-s5+7s4+19s3+25s2+16s+4,Gp=parallel(G1,G2)或Gp=G1+G2%并联,Transferfunction:s5+13s4+57s3+112s2+101s+34-s5+7s4+19s3+25s2+16s+4,15,用零阶保持器将连续系统离散化,num=1;den=conv(10,11);G=tf(num,den);G1=c2d(G,1,zoh)%G1=c2d(sys,Ts,m