How can i get eigen values from simulink model

i made my simulink model and run it in steady state and find initial operating state.i want to find eigen values around this operating point.further if i create small perturbation in system,how can i get eigen value after perturbation. please suggest me

[Kaustubha Govind]

Krishan: Please avoid repeating the same question again. You have already asked a similar question at http://www.mathworks.com/matlabcentral/answers/62258-how-can-i-get-eigenvalues-from-my-simulink-model-after-small-perturbation. It is best to continue related discussions on the same thread.

Answer 1

[Ryan G]

You can use the linear analysis tool to first find the operating point (using operating point snapshot). Then you can linearize the model around this operating point. From here you can find the A matrix from the result and use the EIG function.

[SinanB]

I tried this but Eig(linsys1.A) don't give the expected poles (indicated in the power_PSS example such as 0.64Hz, 1.12Hz and 1.16 Hz). Please note that for the related modes, damping is so small that natural frequencies are approximately the same as the complex part of the poles.

Note that the eigenvalues can also be obtained by damp(linsys1).

Answer 2

[SinanB]

I tried this but Eig(linsys1.A) don't give the expected poles (indicated in the power_PSS example such as 0.64Hz, 1.12Hz and 1.16 Hz). Please note that for the related modes, damping is so small that natural frequencies are approximately the same as the complex part of the poles.

Note that the eigenvalues can also be obtained by damp(linsys1).