文献类型：期刊文献

英文题名：Observer Design for State and Parameter Estimation for Two-Time-Scale Nonlinear Systems

作者：Xiao, Zhenyu[1];Duan, Zhaoyang[1]

机构：[1]East China Univ Sci & Technol, Key Lab Smart Mfg Energy Chem Proc, Minist Educ, Meilong Rd 130, Shanghai 200237, Peoples R China

年份：2024

卷号：12

期号：12

外文期刊名：PROCESSES

收录：;EI(收录号：20245317606050);WOS:【SCI-EXPANDED(收录号:WOS:001384016100001)】；

基金：This research was funded by the National Key R&D Program of China (Program No. 2023YFB3307800) and Shanghai Sailing Program (Program No. 21YF1410000).

语种：英文

外文关键词：parameter estimation; two-time-scale nonlinear system; nonlinear observer; invariant manifold; model reduction; anaerobic digestion; process modeling

摘要：The design and calculation of nonlinear observers for parameter estimation in multi-time-scale nonlinear systems present significant challenges due to the inherent complexity and stiffness of such systems. This study proposes a framework for designing observers for two-time-scale nonlinear systems, with the objective of overcoming the aforementioned challenges. The design procedure involves reducing the original two-time-scale nonlinear system to a lower-dimensional model that captures only the slow dynamics while approximating the fast states through the use of an algebraic slow motion invariant manifold function. Subsequently, an exponential observer can be devised for this reduced system, which is valid for both state and parameter estimation. By employing the output from the original system, this observer can be adapted for online state and parameter estimation for the detailed two-time-scale system. The challenges associated with estimating parameters in two-time-scale nonlinear systems, the complexities of designing observers for such systems, and the computational burden associated with computing observers for ill-conditioned systems can be effectively addressed through the application of this design framework. A rigorous error analysis validates the convergence of the proposed observer towards the states and parameters of the original system. The viability and necessity of this observer design framework are demonstrated through a numerical example and an anaerobic digestion process. This study presents a practical approach for state and parameter estimation with observers for two-time-scale nonlinear systems.