A robust adaptive observer for a class of singular nonlinear uncertain systems

A robust state estimation for a class of uncertain linear time‐invariant descriptor systems

“…For a better evaluation, a comparison between the proposed method and robust adaptive observer (RAO) [14] is also performed. Figure 1 shows the system semistates and their estimations made by the proposed robust observer and the RAO.…”

“…Figure 1 shows the system semistates and their estimations made by the proposed robust observer and the RAO. Based on [14], the dynamic equation of the RAO is considered as follows:…”

“…where ξ RAO is the state vector of the observer and N RAO , H RAO , J RAO , P RAO , and F RAO are the observer parameters that can be determined using lemma 4.1 in Arefinia et al [14] as follows: The RAO in Arefinia et al [14] cannot consider uncertainty in the input matrix. Estimation state errors of the two methods are illustrated in Figure 2.…”

“…The problem of the descriptor system states estimation has attracted the attention of researchers in the last decades. There exist many approaches for observer design and varied models of descriptor systems [12][13][14][15][16][17]. The proportional observer (PO) design has been widely studied for the descriptor systems in previous studies [18,19].…”

“…In the latter case, the unknown parameters have been considered as an independent term in the state equations. In another work [14], the unknown parameters have appeared in the derivative, and the system matrices of the state equations and the input matrix have been supposed to be known.…”