Nonlinear Control of a Non-Minimum-Phase CSTR

Continuous stirred tank reactors (CSTRs) are central components of many plants in the chemical and biochemical industry. These systems may exhibit highly nonlinear dynamics, especially when consecutive and side reactions are present. In this paper, first an example of a complex reaction system in a CSTR which leads to a nonlinear dynamic behaviour with unstable zero dynamics is described in detail. Then one particular control problem for this system is analysed and solved using a novel combination of gain scheduling and linear frequency domain design techniques.