From 7f60ea012dd2524dae921a2a35adbf7ef21f2bb6 Mon Sep 17 00:00:00 2001 From: prashantsinalkar Date: Tue, 10 Oct 2017 12:27:19 +0530 Subject: initial commit / add all books --- 257/CH11/EX11.21/example_11_21.sce | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) create mode 100644 257/CH11/EX11.21/example_11_21.sce (limited to '257/CH11/EX11.21/example_11_21.sce') diff --git a/257/CH11/EX11.21/example_11_21.sce b/257/CH11/EX11.21/example_11_21.sce new file mode 100644 index 000000000..897b351bd --- /dev/null +++ b/257/CH11/EX11.21/example_11_21.sce @@ -0,0 +1,24 @@ +s=poly(0,'s'); +F=syslin('c',[k/((1+0.2*s)*s*(0.05*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 + +k= 10^(26/20) +disp(k,"k marginal = ") + +// for GM=10 dB, the point on the plot without k is 16dB away from 0dB line. +k1=10^(16/20) // 20*log(k1)=-10 +disp(k1,"k for GM=10 is ") + + +// for PM=40degrees, the point on the magnitude plot without k is 12dB away from 0dB line. +k2=10^(12/20) // 20*log(k1)= 6 dB +disp(k2,"for PM=40degrees k is ") -- cgit