Linearizing an MPC model

Initially, I started with an 8th order system and hence my MPC linear model was 8th order. Now I used MATLAB's modelReducer to reduce part of my original system from 4th to 2nd (the system had other components, hence the total order was 8). So, now, my MPC linear model should be of 6th order. But when I try to linearize the reduced model in MPC Designer, I see this error and I cannot make sense what it's trying to say.

Answer 1

[Mykyta Ivaniuk]

I would check for numerical issue, such as zero division. Maybe they appeared after reduction, try to compare 2 models, before and after.

[Deepayan Bhadra]

I had to change the operating point selection and then I didn't get this error anymore. I'm still investigating why.