Identification and Control for Singularly Perturbed Systems Using Multitime-Scale Neural Networks

IEEE Trans Neural Netw Learn Syst. 2017 Feb;28(2):321-333. doi: 10.1109/TNNLS.2015.2508738. Epub 2016 Jan 6.

Abstract

Many well-established singular perturbation theories for singularly perturbed systems require the full knowledge of system model parameters. In order to obtain an accurate and faithful model, a new identification scheme for singularly perturbed nonlinear system using multitime-scale recurrent high-order neural networks (NNs) is proposed in this paper. Inspired by the optimal bounded ellipsoid algorithm, which is originally designed for discrete-time systems, a novel weight updating law is developed for continuous-time NNs identification process. Compared with other widely used gradient-descent updating algorithms, this new method can achieve faster convergence, due to its adaptively adjusted learning rate. Based on the identification results, a control scheme using singular perturbation theories is developed. By using singular perturbation methods, the system order is reduced, and the controller structure is simplified. The closed-loop stability is analyzed and the convergence of system states is guaranteed. The effectiveness of the identification and the control scheme is demonstrated by simulation results.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Artificial Intelligence* / trends
  • Neural Networks, Computer*
  • Nonlinear Dynamics*
  • Time Factors