Korean Journal of Chemical Engineering, Vol.17, No.5, 559-563, September, 2000
Approximation of the Optimal Minimum-phase Output for Control of Nonlinear Nonminimum-phase Processes
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Nonminimum-phase parts are better removed in the feedback loop like the time delay term. For this, Wright and Kravaris [1992] proposed the concept of optimal minimum-phase output to control nonlinear nonminimum-phase processes. However, their optimal minimum-phase output has no analytic solutions for processes with more than three state variables. Here, methods for analytic minimum-phase outputs approximating the optimal ones are proposed, having no limitations in the number of state variables. The proposed methods provide analytic solutions for processes with three state variables and simple numerical solutions for those with more state variables.
Keywords:Nonlinear Nonminimum-phase Process;Input/Output Linearization;ISE Optimal Minimum-phase Output
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