Toward Avoiding Unmeasured Premise Signals in TS Discrete Time Observer Design: State Extension With Nonlinear Output Injection
Résumé
This paper addresses an enhancement of the recently proposed algorithm to overcome the unmeasured premise variables in discrete-time Takagi-Sugeno (TS) systems for observers design [8]. The approach is based on immersion and state extension for tow main objectives: the first one is that the new state vector of the target system after immersion should contain all the state vector of the original system in order to avoid the inverse transformation. Secondly, express the nonlinear system in an adequate form for its transformation in TS form without any unmeasured premise variable. This state extension is performed by introducing simple functions depending on measured variables and their delayed measures. Examples are presented to illustrate the proposed approach.