Feedforward and Feedback Tracking Control of Nonlinear Diffusion−Convection−Reaction Systems Using Summability Methods

Motion planning and design of feedforward and feedback tracking control are studied for a tubular reactor modeled by nonlinear parabolic diffusion−convection−reaction equations. The approach is based on formal power series parametrizations of the system states and inputs, whereby the domain of convergence of the formal series solutions can be greatly extended using appropriate summation methods. As a result, feedforward controls can be determined for a wide range of trajectories and system parameters. Furthermore, on the basis of a reinterpretation of the formal power series parametrization, state feedback with asymptotic tracking control and an observer can be designed for the tubular reactor. On the other hand, following the 2-degrees-of-freedom approach, the feedforward control can be supplemented by a standard output feedback to obtain robust tracking control for tubular reactors with parameter sets reflecting the unpacked tubular reactor up to the real fixed-bed reactor.