Fault Estimation for Discrete-Time Switched Linear Parameter
Varying Systems: An Input-to-State Stability Approach
Yanzheng Zhu Wei Xing Zheng
Abstract— The problem of simultaneous state and fault
estimation for switched linear parameter varying systems
with dwell-time constraint is addressed in the discrete-
time domain in this paper. The polytopic dependence
property is assumed for the parameter variations. By con-
structing a suitable dwell-time-dependent and parameter-
dependent Lyapunov function, sufficient conditions to
guarantee the input-to-state stability (ISS) of the aug-
mented fault estimation error system are established
to meet the ISS-gain performance requirement. Then
simultaneous estimation of the states and the faults
is implemented using an observer-based estimator. The
applicability of the developed fault estimation method is
validated by numerical results.
I. INTRODUCTION
During the past three decades, linear parameter vary-
ing (LPV) systems have gained considerable attention
in the control field due to its attractive modeling ability
for processes with nonlinearities, since the seminal
work is carried out by Shamma in [1]. Closely linked
with the LPV systems, switched systems which involve
a conjunction between continuous dynamics and dis-
crete events have been largely concerned since they
are frequently used to model a wide range of practical
systems, see, for instance, [2], [3]. Regarding LPV
systems with a large parameter variation region, it
is rather difficult to achieve satisfactory performance
requirements through a single controller. It is desired
to develop a group of LPV systems/controllers, such
that each of them corresponds to a specific parameter
subregion. Hence, a new type of systems has emerged,
This work was supported in part by the National Natural Science
Foundation of China under Grant 61603221 and the Australian
Research Council under Grant DP120104986.
Y. Zhu is with the College of Mechanical Engineering and Au-
tomation, Huaqiao University, Xiamen, Fujian, 361021, China, and
also with the School of Computing, Engineering and Mathematics,
Western Sydney University, Sydney, NSW 2751, Australia.
W. X. Zheng is with the School of Computing, Engineering
and Mathematics, Western Sydney University, Sydney, NSW 2751,
Australia.
i.e., switched LPV systems. Consequently, a large num-
ber of practical applications have been reported on the
switched LPV systems itself, and even on the switched
LPV controllers, including missile autopilot systems
[4], wind turbine [5], active magnetic bearing systems
[6], etc.
Compared with the popular average dwell time
(ADT) switching, the more general dwell time (DT)
and even persistent dwell time (PDT) switching prop-
erties have been considered frequently in recent works,
see, for instance, [9]–[13] and references therein. The
DT switching is originally used to deal with the su-
pervisory control issues referring to a family of linear
set-point controllers in [7]. To prevent the undesired
fast switching or chattering, the DT switching scheme
is employed in [8] to stabilize a linear system through
the switching control approach. In [9], the stability
and stabilization problems are addressed for a class
of linear switched systems with DT switching in the
discrete-time domain. By means of quadratic Lyapunov
functions, an upper bound of the minimal DT is de-
termined. However, it cannot directly be extended to
the issues of performance analysis and H
∞
control
containing some complex dynamics, which slows down
the research progress of switched systems under DT
switching. To overcome this issue, some advanced ap-
proaches have been explored more recently, such as the
piecewise Lyapunov function approach [10], the dwell-
time-dependent Lyapunov function approach [11], the
homogeneous rational Lyapunov function approach
[12], etc. Regrettably, in the DT switching scheme,
the corresponding analysis and control have not been
adequately done through these advanced Lyapunov
function techniques when the switched subsystem is
of LPV form.
In reality, the fault is of common occurrence in
many engineering applications, such that the practical
system suffers from loss of stability. In general, a
fault detection and estimation component is provided to
detect and estimate the fault as it occurs. A great deal of
effort has been made to cope with the fault estimation
2019 IEEE Conference on Control Technology and Applications (CCTA)
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