Extremum Seeking Based on Approximated Sign of Gradient of Unknown Plant Maps

Osamu Yamanaka, Yuta Onishi, Yukio Hiraoka, Koichi Hidaka, Hiromitsu Ohmori

研究成果: Conference contribution

3 被引用数 (Scopus)

抄録

This paper presents a novel perturbation-based extremum seeking (ES) based on the smooth approximation of the sign of the gradient of unknown plant maps, which will improve the stability and the control performance of ES. The stability and the convergence speed of conventional sinusoidally perturbed gradient-based ES are very sensitive to the curvature of an unknown plant map, which has motivated the development of improved ES schemes that are less sensitive to the curvature such as Newton-like ES schemes. In this paper, an alternative ES scheme is proposed by estimating the sign of the gradient instead of the gradient itself. The ES scheme not only frees us from taking care of the curvature of the unknown map but also is able to minimize the increase of implementation complexity by just incorporating the signum function for the conventional ES scheme. Moreover, the signum function is replaced by its smooth approximation such as the softsign or a sigmoid function in order not only to suppress chattering phenomena but also to be able to adjust the behavior in the vicinity of an extremum point. It is also shown that the local-stability of the proposed ES scheme can be proved under some mild assumptions for the approximation function. The effectiveness of the proposed ES is demonstrated by some simulation examples for a simple process model and for a complex nonlinear biological wastewater treatment process model.

本文言語English
ホスト出版物のタイトル2020 59th Annual Conference of the Society of Instrument and Control Engineers of Japan, SICE 2020
出版社Institute of Electrical and Electronics Engineers Inc.
ページ249-254
ページ数6
ISBN(電子版)9781728110899
出版ステータスPublished - 2020 9月 23
イベント59th Annual Conference of the Society of Instrument and Control Engineers of Japan, SICE 2020 - Chiang Mai, Thailand
継続期間: 2020 9月 232020 9月 26

出版物シリーズ

名前2020 59th Annual Conference of the Society of Instrument and Control Engineers of Japan, SICE 2020

Conference

Conference59th Annual Conference of the Society of Instrument and Control Engineers of Japan, SICE 2020
国/地域Thailand
CityChiang Mai
Period20/9/2320/9/26

ASJC Scopus subject areas

  • 制御と最適化
  • 器械工学
  • コンピュータ ビジョンおよびパターン認識
  • 信号処理
  • 決定科学(その他)
  • 産業および生産工学

フィンガープリント

「Extremum Seeking Based on Approximated Sign of Gradient of Unknown Plant Maps」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。

引用スタイル