Structural Identifiability of Nonlinear Dynamic Systems

Abstract

Approach to the analysis of nonlinear dynamic systems structural identifiability (SI) under uncertainty is proposed. This approach has difference from methods applied to SI estimation of dynamic systems in the parametrical space. Structural identifiability is interpreted as of the structural identification possibility a system nonlinear part. We show that the input should synchronize the system for the SI problem solution. The S-synchronizability concept of a system is introduced. An unsynchronized input gives an insignificant framework which does not guarantee the structural identification problem solution. It results in structural not identifiability of a system. The subset of the synchronizing inputs on which systems are indiscernible is selected. The structural identifiability estimation method is based on the analysis of framework special class. The structural identifiability estimation method is proposed for systems with symmetric nonlinearities. The input parameter effect is studied on the possibility of the system SI estimation. It is showed that requirements of an excitation constancy to an input in adaptive systems and SI systems differ.