This paper investigates the control problem for a class of highly nonlinear-coupled partial differential equations that describe radiative-conductive heat transfer systems. Thanks to the special structure of the obtained state system, using the Galerkin method for the semi-discretization of PDE and to the differential mean value theorem (DMVT), a new LMI condition is provided for the observer-based controller design. The observer and controller gain are computed simultaneously by solving linear matrix inequality (LMI), i.e a convex problem. Also we provide a reduced order observer based controller that assures global asymptotic stability.
IntroductionRadiative-conduction heat transfer phenomena is usually described by a set of nonlinear partial differential equations (PDEs) with mixed or homogeneous boundary conditions [1]. Due to infinite-dimensional nature of these PDE systems, it is very difficult to apply directly the design methods of lamped parameter systems for their controller design that can be readily implemented in real time with reasonable computing power. Until now, modeling and control of nonlinear PDE systems is still being one of the most challenging areas in control theory. Motivated by the fact that the eigenspectrum of the parabolic spatial differential operator can be partitioned into a finite-dimensional slow one and an infinite-dimensional stable fast complement, most of the existing results on the control design for parabolic PDE systems involve initially the application of the spatial discretization techniques (predominantly Galerkin's method) to the PDE system to derive ordinary differential equation (ODE) systems that describe the dominant dynamics of the PDE system. These ODE systems are subsequently used as the basis for the synthesis of the finite-dimensional controllers. For example, [2,17,3] studied the finite-dimensional control problems of linear parabolic PDE systems. In [18], Ray also discussed the linearization method for the control design of a class of nonlinear parabolic PDE systems. However,