In the field of model order reduction, if all the poles lie at the same point for a higher order system, then to reduce the order of the system is very difficult. Can anyone tell me which method is suitable to reduce the system, especially in frequency domain methods?
Good evening,
If the system has a rational transfer function, then its order can be reduced by using minimal realizations technique
You need to find the coprime fraction expression
Also, poles placement technique can be used to re-construct your system with different poles
Regards.
You could get an approximation: a first or second order system plus delay, in case you have multiple repeated poles, I presume you mean real poles. But it depends on the system, and i/o pair, the above tends to work quite well for process plants (see work by Skogestad). Minreal will give you a system with states both ctrlb and obsv, I.e. removes obsolete uncrtb and unobsv states (it may well remove some of those poles). Otherwise you need to refer to the appropriate model reduction methods (matlab has some good help on this as well).
By applying Pole clustering method, I hope we can reduced the system.
I think the suggestion of Prof.A. Zolotas will work best , if you are thinking of repeated stable real poles. May also try the Stability Equation method [See the Journal of the Franklin Institute].
- Badges
- Science topic
- Similar topics
- Mathematical Sciences
- Control Theory
- Control Systems