plotting graph in simulink

I have to plot graphs in simulink the graphs is i the link

http://imgur.com/nVY8q

how can we plot the graph in simulink,if not possible in simulink ,please tell how to plot in matlab m file

Answer 1

This is a plot of a step response of second order system, you can use step command in a for loop, varying the damping coefficient sigma from 0 to 1

hold on;
sigma=.5;
for k=1:5
w0=1;
sigma=sigma+.1;
N=[w0];
D=[1 2*sigma*w0 w0^2]
step(N,D)
end
grid

you can get the same figure in simulink, by simulating 5 ore more second order transfer function with differents damping coefficient sigma, and use one scope and one multiplexer

Thanks Azzi But those grapg are in negative region,please tell how t0 plot

What do you mean by they are in negative region, and show correctly the image you want to make.

my graph is

http://www.sendspace.com/file/44fh7a

in this non-stable region B is in negative axis..

non-stable region A is in positive axis..

is it possible to get graph like this..else plz tell hoe to plot non-stable region B in negative axis

It appears that is a frequency response, what your graph is supposed to represent?

ya azzi its a frequency response,it represents non stability regions during power flow

You can't just draw this plot, you must provide the frequency response

is it possible to draw non stability region B in negative region

Answer 2

MATLAB might be more appropriate if you want to control the line styles. See Specifying Line Style.

I need to plot like given in image ,the code to plot such graphs,can u help me please

Here is documentation on getting started with plotting in Matlab. Here is another link on plotting.

I know to plot different graphs with line specified ,but how to get the same shape as i have posted

You put it together yourself, calculating where all the lines should go.

There is no built-in plot of that style that I know of in MATLAB (but it is possible it exists in a toolbox somewhere or in Simulink somewhere and I just have not run across it yet.)

Pat: Are you asking us to identify the function that has been plotted? That might be difficult to do.