Nonlinear model predictive control and H-infinity robust control for a post-combustion CO2 capture process

作者：Zhang Qiang; Turton Richard; Bhattacharyya Debangsu^*

来源：International Journal of Greenhouse Gas Control, 2018, 70: 105-116.

DOI：10.1016/j.ijggc.2018.01.015

• Post-combustion CO2 capture
• Model predictive control
• H-infinity robust control
• Model uncertainties

This work focuses on the design of a nonlinear model predictive controller (NMPC) and an H-infinity robust controller for an MEA-based CO2 capture process. The model used in the NMPC is a nonlinear, additive, autoregressive model with exogenous (NAARX) inputs. Uncertainties are unavoidable in chemical processes. Therefore, a robust controller is designed for the CO2 capture process based on mu-synthesis with a DK-iteration algorithm. The effects of uncertainties due to measurement noise and model mismatches are evaluated for both the NMPC and robust controller. The system disturbances include a number of input and output disturbances such as the flue gas flowrate and composition and variable capture targets. This study shows that the tradeoff between the fast tracking performance of the NMPC and the superior robust performance of the robust controller must be considered while designing the control system for the CO2 capture units.

• 出版日期2018-3