|Discrete-time Linear Descriptor System Unknown Input Observer Design: an Auxiliary Output-based Approach
Jiancheng Zhang, Fanglai Zhu, Jun Li*, and Xiaohang Li
International Journal of Control, Automation, and Systems, vol. 15, no. 6, pp.2599-2607, 2017
Abstract : "This paper develops a new unknown input observer (UIO) design method for a class of discrete-time
linear descriptor systems when the observer matching condition is not satisfied. By equivalent transformations, the
state and unknown input observations of the descriptor system are changed to the UIO design problem for a general
linear dynamic system firstly. Then based on some further discussion on the concept of the system left invertibility,
a new auxiliary output vector is constructed which allows us to remove the unknown inputs from the dynamic
equation, and thereby a Luenberger-type observer can be constructed. One of the advantages of the present method
is that it can work only under the single strongly detectable condition. Finally, a simulation example is given to
verify the effectiveness and show the superiorities of our methods."
Auxiliary output, descriptor system, left invertibility, observer matching condition, state estimation.