Parallel Solution of Robust Nonlinear Model Predictive Control Problems in Batch Crystallization
AbstractRepresenting the uncertainties with a set of scenarios, the optimization problem resulting from a robust nonlinear model predictive control (NMPC) strategy at each sampling instance can be viewed as a large-scale stochastic program. This paper solves these optimization problems using the parallel Schur complement method developed to solve stochastic programs on distributed and shared memory machines. The control strategy is illustrated with a case study of a multidimensional unseeded batch crystallization process. For this application, a robust NMPC based on min–max optimization guarantees satisfaction of all state and input constraints for a set of uncertainty realizations, and also provides better robust performance compared with open-loop optimal control, nominal NMPC, and robust NMPC minimizing the expected performance at each sampling instance. The performance of robust NMPC can be improved by generating optimization scenarios using Bayesian inference. With the efficient parallel solver, the solution time of one optimization problem is reduced from 6.7 min to 0.5 min, allowing for real-time application. View Full-Text
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Cao, Y.; Kang, J.; Nagy, Z.K.; Laird, C.D. Parallel Solution of Robust Nonlinear Model Predictive Control Problems in Batch Crystallization. Processes 2016, 4, 20.
Cao Y, Kang J, Nagy ZK, Laird CD. Parallel Solution of Robust Nonlinear Model Predictive Control Problems in Batch Crystallization. Processes. 2016; 4(3):20.Chicago/Turabian Style
Cao, Yankai; Kang, Jia; Nagy, Zoltan K.; Laird, Carl D. 2016. "Parallel Solution of Robust Nonlinear Model Predictive Control Problems in Batch Crystallization." Processes 4, no. 3: 20.
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