Respected, I plotted the graph between time and current by taking values from electric load using Simulink model in matlab. Now i want to plot the graph between voltage and current that is known as VI curve.so now the problem is the axis. So kindly tell me how can i change the X axis scale of time into voltage scale.thanks.
Regards Abbas Tausif
From your question it is not very clear how your are acquiring your data, thus my answer can only be so detailed.
This is how I would solve this problem: In simulink use a clock connected to a "To Workspace" block to record record time.
Use another "To Workspace" block to record the load (I'm not sure if you mean power or impedance here).
set format of both "To Workspace" blocks to array.
After running the simulation you will have two variables in MATLAB (time and load), then using V=IR or P=IV you can work out arrays for voltage and current.
Finally you can plot a graph using the arrays you calculated for V and I in MATLAB using plot(time,current) or plot(voltage,current) ect...
I hope this helps.
XY-GraphBlock. – Robert Seifert