Canadian Journal of Chemical Engineering, Vol.84, No.6, 704-714, 2006
Estimation of variance reduction opportunities through cascade control
We describe an approach that is useful in deciding if significant benefits, in terms of control loop performance index (through variability reduction), will be achieved by a change in control loop configuration from simple feedback (SFB) to cascade control. The problem is considered in a stochastic setting and solved using the variance decomposition technique. The proposed methodology requires only routine operating data from an existing simple feedback control loop and knowledge of the process delays. Several simulation examples and one experimental case study exemplify the utility of this approach.
Keywords:variance decomposition;control loop performance assessment;performance monitoring;minimum variance control;cascade control