Nonintrusive frequency analysis for variable pairing on a distillation column

This paper describes a nonintrusive plant analysis technique for variable pairing that relies on power spectrum frequency analysis. The development of the method is described and guidelines for the implementation of the method are presented. Information gathered from the frequency analysis is used in variable pairing to ensure minimal impacts from unmeasured disturbances. Specifically, the nested epsilon decomposition method for variable pairing is used. This nonintrusive analysis method is implemented on a pilot plant distillation column. The results of the pilot plant test are used in the decoupling of a multiloop control system.