fig527.m

realize analysis and design for computer-controlled system

% Generates Fig 5.27
% Computer Controlled Systems (3rd ed)
% Author: B. Wittenmark
% Last edit: 1997-07-04
% Copyright (c) 1996 by K. J. 舠tr鰉, B. Wittenmark and
% Department of Automatic Control, Lund Institute of
% Technology, Lund, Sweden

newplot;clf;
lw=0.9;
set(gcf,'PaperUnits','centimeters','PaperPosition',[2 2 13 9.5])
set(gcf,'Units','centimeters','position',get(gcf,'PaperPosition'))

h=0.5;

r1=-2.0095251;
r2=1.6353356;
r3=-0.63529099;
r4=0.10539691;
r5=0;
s0=1.9207519;
s1=-4.7306366;
s2=4.7691955;
s3=-2.1822977;
s4=0.45055132;
s5=0;
spol=[s0 s1 s2 s3 s4];
rpol=[1 r1 r2 r3 r4];
aproc=conv([1 -1],[1 -1.7124 0.9512]);
afilt=[1 -0.7505 0.2466];
apol=conv(aproc,afilt);
bpol=0.0001420*conv(conv([1 12.1314],[1 1.3422]),conv([1 0.2234],[1 -0.0023]));
blg=conv(bpol,spol);
alg=conv(apol,rpol);
wrad1=logspace(-3,pi,300)/h;
[mag1,ph1,wrad1]=dbode(blg,alg,h,wrad1);


s0=-6.5531193;
s1=14.817715;
s2=-11.892218;
s3=4.577591;
s4=-0.70196741;
s5=0;
r1=-1.5287662;
r2=1.0527504;
r3=-0.36961555;
r4=5.46430042e-02;
r5=0;
rpol=[1 r1 r2 r3 r4];
spol=[s0 s1 s2 s3 s4];
alg=conv(apol,rpol);
blg=conv(bpol,spol);
wrad2=logspace(-3,pi,500)/h;
[mag2,ph2,wrad2]=dbode(blg,alg,h,wrad2);

subplot(2,1,1)
loglog(wrad1,mag1,'m-',wrad2,mag2,'k--','Linew',lw)
axis([0.01 10 0.001 100])
set(gca,'Fontsize',9,'Fontname','NewCenturySchlbk');
set(gca,'ytick',[0.01 1 100]);
set(gca,'xtick',[0.01 0.1 1 10]);
ylabel('Gain','Fontname','NewCenturySchlbk','Fontsize',9)
xlabel('Frequency, rad/s','Fontname','NewCenturySchlbk','Fontsize',9)
hold on
plot([0.01 10],[1 1],'k:','Linew',lw)