The Swept-sine-excitation-based Frequency Response Estimation for Nonlinear SIMO Systems

Abstract

This paper deals with the identification of a nonparametric model of the system in the frequency domain. The proposed solution handles problems arising from common identification experiment requirements, such as the need to keep the experiment in the neighborhood of the chosen operating point, the identification of a system with multiple outputs, and suppression of the influence of small nonlinearities.The proposed method uses a swept sinusoidal signal for excitation and an extended time-varying state observer to filter out higher harmonic components.The complete algorithm has been implemented as a function block for identification of mechatronic and power systems in the REXYGEN control system of the Czech SME company REX Controls.