Application of Quasi Infinite Horizon Nonlinear Model Predictive Control to Unstable Tank Reactor

Ensuring asymptotic stability of nominal nonlinear model predictive control scheme is not a trivial task. Various approaches like terminal equality constraint, terminal inequality constraint and without terminal inequality constraint are available in the literature. Current paper details application of two novel approaches for the terminal set computation of discrete time quasi infinite horizon nonlinear model predictive control formulations around open loop unstable equilibrium condition. Case study used for demonstration is a standard continuous stirrer tank reactor system. Fundings are displayed without any noise case i.e., nominal case and for with input noise and state noise i.e., robust case. Studies validate and verify the asymptotic stability result. State trajectories for with noise case i.e., robust cases remained close to the trajectories in without noise case i.e., nominal case as per expectation (because of the bounded disturbances).