Fourier and Laplace 425
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Amplitude (amps) Amplitude (volts)
Amplitude (volts) Amplitude (volts)
time (sec)
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time (sec)
vl(t) versus tvc(t) versus t
i(t) versus t vr(t) versus t
FIGURE 4.71
Plots of i(t), vl(t), vr(t), and vc(t) of Example 4.16.
plo t(t,vlt);title(‘vl(t) v s t’);yla b e l(‘A m plitu d e (v olts)’);
xlabel(‘time (sec)’)
%plot of VC(t) vs t
VCnum = [0 0 0 0 300];
VCden = [1 2 19 18 90];
vct = impulse(VCnum,VCden,t);
subplot(2,2,4)
plo t(t,v c t);title(‘v c(t) v s t’);yla b e l(‘A m plitu d e (v olts)’);
xlabel(‘time (sec)’)
figure(2)
subplot(2,1,1)
plot(t,it,t,vrt,t,vlt,t,vct)
title(‘Plots of: i(t) vs.t, vr(t) vs.t, vl(t)vs.t, and vc(t) vs.t’)
axis([0,5,-20,20])
ylabel(‘Amplitude (amps/volts)’)
subplot(2,1,2)
vsourse = vrt+vlt+vct;
plot(t,vsourse);
title(‘[vr(t)+vl(t)+vc(t)] vs. t (verifies KVL)’)
xlabel(‘time (sec)’);
ylabel(‘ Amplitude (volts)’)
axis([0 5 -12 12])
The script fi le RLC_series is executed and the results are shown in Figures 4.71
and 4.72.