Authors:
Kemin Zhou,
Volume: 1, Page 4120 Paper number 2091
Abstract:
In this paper, we propose a new feedback controller architecture. The
distinguished feature of our new controller architecture is that the
controller design for performance and robustness can be done separately
which completely overcome the conflict between performance and robustness
in the traditional feedback framework. The controller architecture
includes two parts: one part for performance and the other part for
robustness. The controller architecture works in such a way that the
feedback control system will be solely controlled by the performance
controller when there is no model uncertainties and external disturbances
and the robustification controller will only be active when there is
model uncertainties or external disturbances.
Authors:
Mufeed Mahmoud,
Jin Jiang,
Youmin Zhang,
Volume: 1, Page 4126 Paper number 1466
Abstract:
In this paper, an optimal control law is designed for Fault Tolerant
Control Systems with Markovian Parameters(FTCSMP). The matrix maximum
principle is used to minimize an equivalent deterministic cost function.
Three scenarios are considered. The first assumes that both the failure
process and the Fault Detection and Isolation (FDI) process are accessible
for controller. In the second scenario, the controller is reconfigured
based on the decisions of the FDI process and does not need an accessible
failure process. The case where the FDI process itself is not able
to give any decision due to physical malfunction or excessive computational
time is the third scenario. In these scenarios, optimal control laws
are developed to reduce the risk of losing system stability. A computational
algorithm is constructed to calculate the optimal control law.
Authors:
Zhenyu Yang,
Jakob Stoustrup,
Volume: 1, Page 4132 Paper number 1462
Abstract:
From the system recoverable point of view, this paper discusses robust
reconfigurable control synthesis for LTI systems and a class of nonlinear
control systems with parametric and additive faults as well as derivations
generated by FDI algorithms. By following the model-matching strategy,
an augmented optimal control problem is constructed based on the considered
faulty and fictitious nominal systems, such that the robust control
design techniques, such as H_(infinity) control and mu synthesis, can
be employed for the reconfigurable control design.
Authors:
Christian Commault,
Jean-Michel Dion,
Olivier Sename,
Reza Moteyian,
Volume: 1, Page 4138 Paper number 1083
Abstract:
We consider here the Fault Detection and Isolation (FDI) problem for
linear systems with disturbances. We try to design a set of residuals
through a bank of observers, in such a way that the transfer from the
disturbances to the residuals is zero and the transfer from the faults
to the residuals is diagonal. We deal with this problem when the system
under consideration is structured, that is, the entries of the matrices
which define the system are either fixed zeros or free parameters.
To structured systems one can associate in a natural way a directed
graph. We are then able to give a necessary and sufficient condition
under which the FDI problem has a solution for almost any value of
the free parameters. This condition is simply expressed in terms of
particular paths in the associated graph.
Authors:
Steven X. Ding,
Paul M. Frank,
Eve L. Ding,
Torsten Jeinsch,
Volume: 1, Page 4144 Paper number 1976
Abstract:
In this paper, problems related to the fault detection in dynamic systems
with unknown inputs are studied. Instead of designing fault detection
systems from the viewpoint of increasing the system robustness against
unknown inputs and the sensitivity to the faults, an approach is proposed,
which allows us to design fault detection systems based on a trade-off
between the false alarm rate and the missed detection rate. A further
study on the relationships between the approach proposed and the existing
optimization approaches demonstrates that the approach proposed in
this paper provides us not only with a unified solution to the existing
approaches but also with the best solution among these approaches in
view of minimizing the missed detection rate under a given false alarm
rate.
Authors:
Olivier Adrot,
Didier Maquin,
José Ragot,
Volume: 1, Page 4150 Paper number 1487
Abstract:
This paper deals with an original fault detection and isolation method,
allowing to take the structure and the range of model uncertainties
into account. We focus on static and structured uncertain models, where
each parameter uncertainty is described by a bounded variable. In order
to de-couple residuals from unknown physical variables, a parity space
approach is proposed, where the parity matrix depends on uncertain
parameters. Because of this membership approach, called bounding approach,
residuals represent a set of feasible behaviours and define therefore
the normal operating domain of the studied physical system. To simplify
its evaluation and work on a simple domain such as a parallelotope,
residuals are linearised in the bounded variables and a reduction procedure
is applied to decrease their complexity. Once the constraints defining
this domain are determined, consistency tests for fault detection and
isolation are built.
Authors:
Hao Ye,
Ping Zhang,
Steven X. Ding,
Guizeng Wang,
Volume: 1, Page 4156 Paper number 1308
Abstract:
In this paper, problems related to the design of robust residual generators
have been studied. The main objective of our study is to make use of
the simple time domain design form of the parity relation based approach
and the frequency domain analysis known by the H2- optimization approach,
in order to improve the system performance without an essential increase
in computation. We establish a relationship between the parity relation
based and the H2-optimal residual generators and show that the optimal
parity vector converges to the H2-optimal post-filter when the order
of the parity vector tend to infinity. Making use of the fact that
the H2-optimal post- filter is a narrow band filter and the well known
time-frequency domain properties of Wavelet Transform, a time-frequency
domain approach is developed, which allows us to design a residual
generator based on Wavelet Transform. The significant property of such
kind of residual generators is its simple form, low order and high
performance. The main results are illustrated by examples.
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