Pre-stabilised Predictive Functional Control for Open-loop Unstable Dynamic Systems

Recent Developments in Tuning Methods for Predictive Functional Control

“…Indeed, this was also recognised in some PFC proposals [9,24], although those implementations were clumsy and contained other inconsistencies. More recently, it was suggested that researchers should investigate this more systematically in a PFC context [13,14,32]. The basic idea is to form an internal feedback loop, such as in Figure 2, and then to form an outer loop based on PFC to determine the loop input signal v k .…”

Predictive functional control for challenging dynamic processes using a simple prestabilization strategy

“…This section presents the concept of pre‐stabilisation in the context of PFC and proposes a systematic design framework, based on the initial proposal, 21 to cater for a variety of difficult open‐loop dynamics.…”

“…The current pole placement proposal is based on the analytical approach of feedback compensation presented in reference 21 . Assume that a $$$ \left(n-1\right) $$$th‐order bi‐proper compensator $$$ C(z) $$$ is used to modify the open‐loop model $$$ {G}_0(z) $$$, as shown in Figure 3, resulting in the prestabilized transfer function $$$ {G}_{s,0}(z) $$$, with a smooth and monotonically convergent prediction behavior.…”

“…A more recently proposed alternative, building on common practice in the more mainstream MPC literature, 16,17 is to prestabilize the undesirable open‐loop predictions using an internal feedback compensation loop. While this concept within PFC has largely been limited to first‐order unstable 18 or integrator dynamics 19,20 and very simple prestabilization compensators, one recent study 21 has extended its scope to higher‐order unstable dynamics using some more involved inner compensation schemes, resulting in promising performance attributes but at the cost of increased constraint handling complexity. Another recent study 22 has suggested an improved and more meaningful parameter tuning after prestabilization; 22 a benefit that significantly outweighs the slight intricacy in constraint handling that may arise due to the use of complicated internal loops.…”

“…Nevertheless, the need for a more thorough investigation in this context is evident; an objective which the current paper aims to accomplish. Therefore, the primary contribution, building on the recent proposal, 21 is the development of a systematic but simple PFC design framework for underdamped and unstable dynamic processes, integrating an intuitive tuning algorithm along with straightforward guidelines to perform efficient constraint management.…”