| US 7,454,253 B2 | ||
| Fast performance prediction of multivariable model predictive controller for paper machine cross-directional processes | ||
| Junqiang Fan, Vancouver (Canada) | ||
| Assigned to Honeywell ASCA Inc., Mississauga, Ontario (Canada) | ||
| Filed on Mar. 30, 2006, as Appl. No. 11/393,474. | ||
| Prior Publication US 2007/0239310 A1, Oct. 11, 2007 | ||
| Int. Cl. G06F 19/00 (2006.01) | ||
| U.S. Cl. 700—29 [702/150; 702/12] | 25 Claims |
| 1. A method of fast approximating the performance of a cross-direction machine-direction multivariable model predictive controller
(CDMD MPC) for a spatially-distributed sheet process that comprises the steps of:
(a) identifying a process model for the spatially-distributed sheet process which is employed in a sheetmaking machine that
forms a sheet of material and that comprises:
(i) at least two sets of actuator arrays each distributed adjacent the material in the cross direction (CD), wherein each
set of actuator arrays is controllable to vary properties of the material;
(ii) means for measuring and acquiring properties data about the properties of the material in the cross direction;
(iii) CDMD MPC for the spatially-distributed sheet process providing CD control to the multiple-array cross-directional process,
wherein the MPC, in response to signals that are indicative of the properties data, provides signals to the at least two sets
of actuator arrays to vary properties of the material; and
(iv) means for fast approximating the performance of the CDMD MPC, based on the process model for the spatially-distributed
sheet process and tuning parameters and constraints, that includes means for calculating a steady-state spatial performance
of the CDMD MPC and means for calculating a dynamic performance of the CDMD MPC;
(b) inputting tuning parameters and constraints into the CDMD MPC;
(c) calculating steady-state spatial performance for the CDMD MPC for different sheet property modes that includes CD only
mode, machine-direction (MD) only mode, and CD and MD mode;
(d) calculating a dynamic performance for the CDMD MPC;
(e) inputting optimal tuning parameters to the CDMD MPC; and
(f) controlling the sheetmaking machine with the CDMD MPC.
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