1 files changed, 31 insertions, 0 deletions
diff --git a/257/CH11/EX11.11/example_11_11.sce b/257/CH11/EX11.11/example_11_11.sce
new file mode 100644
index 000000000..cb661deb9
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+++ b/257/CH11/EX11.11/example_11_11.sce
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+s=poly(0,'s'); 
+F=syslin('c',[1/((1+s)*s*(0.1*s+1))])                  //without k
+
+fmin=0.1;                                        //Min freq in Hz
+fmax=20;                                          //Max freq in Hz
+
+scf(1);clf;
+bode(F,fmin,fmax);                                //Plots frequency response of open-loop system in Bode diagram
+
+show_margins(F)                                //display gain and phase margin and associated crossover frequencies
+
+// TO FIND VALUE OF K
+
+// for GM=30 dB, the point on the plot without k is 10dB away from 0dB line.
+k1=10^(-10/20)                                      // 20*log(k1)=-10
+disp(k1,"k for GM=30 is ")
+F1=syslin('c',[(k1)/((1+s)*s*(0.1*s+1))])
+
+[PhaseMargin,freqPM]=p_margin(F1)                
+disp(freqPM*2*3.14,"corresponding omegaGC")
+disp(PhaseMargin,"PM=")
+
+// for PM=30degrees, the point on the magnitude plot without k is 6dB away from 0dB line.
+k2=10^(6/20)                                      // 20*log(k1)= 6 dB
+disp(k2,"for PM=30degrees k is ")
+F2=syslin('c',[(k2)/((1+s)*s*(0.1*s+1))])
+
+[PhaseMargin,freqPM]=p_margin(F2)                
+disp(freqPM*2*3.14,"corresponding omegaGC")
+[GainMargin,freqGM]=g_margin(F)
+disp(GainMargin,"GM=")
+\ No newline at end of file