Fast Multi-Order Stochastic Subspace Identification⋆

Abstract

AbstractStochastic subspace identification methods are an efficient tool for system identification of mechanical systems in Operational Modal Analysis (OMA), where modal parameters are estimated from measured vibrational data of a structure. System identification is usually done for many successive model orders, as the true system order is unknown and identification results at different model orders need to be compared to distinguish true structural modes from spurious modes in so-called stabilization diagrams. In this paper, this multi-order system identification with the subspace-based identification algorithms is studied and an efficient algorithm to estimate the system matrices at multiple model orders is derived.