MATLAB: How get state-space model from simulink model

kundursimulink

Hello.
How can I get a state space model from simulink power_PSS model? power_PSS is a Kundur two area model. I tried to use linmod() and linmod2() but get error message
??? Error using ==> fileparts at 17 Input must be a row vector of characters.
Error in ==> load_system at 19 [path, sys, ext] = fileparts(sys); %#ok<NASGU>
Error in ==> getLinNormalModeBlocks at 22 load_system(mdl);
Error in ==> dlinmod at 107 [normalblks,normalrefs] = getLinNormalModeBlocks(model);
Error in ==> linmod at 60 [varargout{1:max(1,nargout)}] = dlinmod(model, Ts, varargin{:}, Args);
Thank you!

Best Answer

>> linmod('power_PSS')
SimPowerSystems processing circuit #1 of power_PSS ...
Computing state-space representation of linear electrical circuit ...
(68 states ; 35 inputs ; 47 outputs ; 9 switches)
Computing steady-state values of currents and voltages ...
Building the Simulink model inside "powergui" block ...
Ready.
ans =
a: [252x252 double]
b: [252x0 double]
c: [0x252 double]
d: []
StateName: {252x1 cell}
OutputName: {0x1 cell}
InputName: {0x1 cell}
OperPoint: [1x1 struct]
Ts: 0