State and unknown input estimation for a class of infinitely unobservable descriptor systems using two observers in cascade. Issue 18 (December 2017)

• Record Type: Journal Article
• Authors: Ooi, Jeremy H.T.; Tan, Chee Pin; Chua, Wen-Shyan; Wang, Xianghua
• Is Part Of: Journal of the Franklin Institute. Volume 354:Issue 18(2017)
• Page Start: 8374
• Page End: 8397
• Publication Date: 2017-12
• Subjects: Science -- Periodicals; Technology -- Periodicals; Patents -- United States -- Periodicals; 505
• DOI: 10.1016/j.jfranklin.2017.09.017
• Languages: English
• ISSNs: 0016-0032

Abstract

Abstract: This paper presents an observer scheme for state and unknown input estimation for a class of infinitely unobservable descriptor systems. Though there are observer schemes for infinitely unobservable systems, they may require a higher number of outputs, which could prove restrictive. The proposed scheme in this paper consists of two observers – the first one being a standard linear observer for descriptor systems. Signals from that observer are processed and found to be the output of an analytical regular state-space system. Then, the second observer, which is a sliding mode observer, is applied to estimate the state and unknown input. Necessary and sufficient conditions associated with the scheme are also derived. Finally, a simulation example is presented to demonstrate the effectiveness of the scheme.