Flatness-based disturbance decoupling for heat and mass transfer processes with distributed control

This paper deals with the control of heat and mass transfer processes. The mathematical model of a process is presented by a distributed parameter system described by inhomogeneous parabolic partial differential equations in one-dimensional space. The control input is represented by a source function, while the boundary inputs correspond to disturbances in the system of interest. The flatness of these systems is studied. In contrast to the systems with boundary control, the flat output for such systems does not coincide with the control output and cannot be uniquely defined. A part of the dynamic relations describes the influence of the boundary inputs, i. e. disturbances, on the control output. In the paper the approach for the decoupling of the control output from the disturbances on the bounds is proposed. The approach is based on the examination of the inverse dynamics of the system and the design of the observer for the state variables reproducing the influence of the disturbance. Some numerical simulations are included and demonstrate the efficiency of the proposed approach