Matlab / Simulink Block Error

Hey guys,

I don't understand which parameters are wrong. I want to simulate a isothermal expansion. Here I got this Error:

A valid state attribute should be a non-missing string array, a character vector, a cell array or a valid MATLAB structure.

Component:Simulink | Category:Block error

This is my Matlab Code:

clc, clearvars

% Parameter deklarieren

V0 = 0.001; % Anfangsvolumen [m^3]

Q = 1; % Heizleistung [W]

Rs = 287.058; % spezifische Gaskonstante für Luft [J/(kg*K)]

T = 293.15; % Anfangstemperatur [K]

p = 100000; % Anfangsdruck [Pa]

Tsim = 200; % Simulationsdauer [s]

h = 0.1; % Schrittweite [s]

% Simulink-Modell laden

open_system('isotherm_expansion');

% Anfangsbedingungen setzen

set_param('isotherm_expansion/Integrator', 'InitialCondition', '0.001');

set_param('isotherm_expansion/Gain', 'Gain', num2str(Q/(Rs*T)));

% Simulationszeit konfigurieren

set_param('isotherm_expansion', 'StopTime', num2str(Tsim));

% Simulation ausführen

sim('isotherm_expansion');

% Simulationsergebnisse speichern

t = V.time; % Zeitvektor

v = V.signals.values; % Volumenvektor

% Ergebnisse plotten

plot(t,v);

title('Volumenänderung während einer isothermen Expansion');

xlabel('Zeit [s]');

ylabel('Volumen [m^3]');

My Blocks + Parameters:

Integrator:

Sum:

Gain:

Hope that you can help me.

Thanks a lot! Cheers,

Alessandro

Answer 1

[Fangjun Jiang]

The "State Name" parameter of the Integrator block, where you set as "V0", should not be a value. It is a "Name". It should be something like " 'Anfangsvolumen' ", like e.g. 'Position' in the dialog prompt.