Development of model based control in commercial control systems

In industrial control systems PID-control remains the prevalent strategy, also for processes that would benefit from model based control. The purpose of this thesis is to evaluate whether model based control can be readily implemented in an industrial control system. To this end a simulated surge tank with a simulated industrial control system is studied. For evaluation two scenarios with specified objectives are selected. Following a review of LQR and versions of MPC, Predictive Functional Control (PFC) is considered the most suitable for implementation. PFC is a form of MPC developed with industrial applications in mind and therefore has several advantages for implementation in an industrial control system. Controllers for the surge tank-system are developed and implemented in the control system. Basic analysis of stability, sensitivity and robustness suggests that PFC has some advantages that might be important in a non-simulated implementation. Compared with PID-controllers adjusted for control performance, PFC does not show any notable improvements in performance. In conclusion, it is possible to implement model based control in an industrial control system and with PFC the implementation is considered easy