Dissertação
Projeto de controladores tolerantes a falhas baseados em observador : uma abordagem em faixas de frequência finita
Fecha
2021-07-30Autor
Caio Mariano da Silva Anastácio
Institución
Resumen
This work proposes to fill an existing gap in the literature by introducing a methodology to
fault-tolerant control based on observer design in predefined frequency ranges with guar-
anteed H-infinite performance for continuous-time switched systems. The proposed approach
makes use of the states and the estimation fault from the synthesized observer to compose
a control law, which ensures effectiveness in rejecting external disturbances and compen-
sating for the effects of faults in low, middle and high frequency domains. Furthermore,
to ensure the asymptotic stability of the switched system, the switching signal respects
the mode-dependent average dwell time (MDADT) condition, ensuring that the system
remains a minimum time in each mode and avoiding instabilities concerning arbitrary
switching. The problem is structured in such a way that, in closed-loop, the observer and
the controller can be synthesized separately. For this purpose, initially, the proposed ob-
server is designed to obtain the estimates of states and faults in specific frequency ranges
from the generalized Kalman-Yakubovich-Popov lemma. Subsequently, the fault-tolerant
controller with H-infinite guaranteed cost is designed, ensuring closed-loop stability for switched
systems under MDADT constraints. In both designs, the conditions are described in lin-
ear matrix inequalities form. Illustrative examples taken from the literature are used to
demonstrate the effectiveness and applicability of the proposed approach.