small signal model verification for VSI grid-connected

Hi everyone, I have developed the mathematical model (state-space model) of the system in the attached picture and I'm trying to verify the model with the SIMULINK model. I found the eigenvalues of the A-matrix and the imaginary part (frequency) is exactly same as the Simulink model, but the real part(decay) wasn't same.Hence, can anyone help me what can be the problem? or is there any other way to validate the mathematical model? Thank you in advance