Sensitivity of MIMO controller performance to model-plant mismatch, with applications to paper machine control

Model-based controllers based on incorrect estimates of the true plant behaviour can be expected to perform badly. This work quantifies the performance deterioration for a certain class of MIMO systems. Performance is measured using a Minimum Variance index and a closely related user-specified criterion. Under reasonable conditions, the performance of each output component in a MIMO system can be analysed independently. We define a sensitivity measure that relates system performance to model-plant mismatch, and use it to explore this sensitivity for three realistic types of parametric modelling errors. Next, we suggest a quantitative method that compares a system's actual output to its desired response in a transient setting. The performance of the transient response is demonstrably more sensitive to the model-plant mismatch than the steady state performance. The results are illustrated on industrial paper machine data.

[1]  G.A. Dumont,et al.  Control loop performance monitoring , 1996, IEEE Trans. Control. Syst. Technol..

[2]  T. J. Harris,et al.  Performance assessment of multivariable feedback controllers , 1996, Autom..

[3]  T. Harris.  Assessment of Control Loop Performance , 1989 .

[4]  Biao Huang,et al.  Performance Assessment of Control Loops , 1999 .

[5]  C. T. Seppala,et al.  A review of performance monitoring and assessment techniques for univariate and multivariate control systems , 1999 .

[6]  S. Joe Qin,et al.  Control performance monitoring — a review and assessment , 1998 .

[7]  R. Bhushan Gopaluni,et al.  Sensitivity of controller performance indices to model-plant mismatch: An application to paper machine control , 2014, 2014 American Control Conference.

[8]  Lane Desborough,et al.  Control performance assessment: a method to diagnose loop problems is discussed , 1994 .

[9]  Tore Hägglund,et al.  Quantitative Analysis of Influences of Model Plant Mismatch on Control Loop Behavior , 2012 .

[10]  K. Åström.  Introduction to Stochastic Control Theory , 1970 .

[11]  Ma Huafang,et al.  A method of control performance diagnosis to discriminate between model-plant mismatch and unmeasured disturbance , 2011, 2011 Chinese Control and Decision Conference (CCDC).

[12]  Thomas J. Harris,et al.  Interpretations of multivariate performance assessment indices , 2009 .

[13]  Sirish L. Shah,et al.  Quantifying the impact of model-plant mismatch on controller performance , 2010 .

[14]  Tore Hägglund.  Automatic Monitoring of Control Loop Performance , 1994 .

[15]  Biao Huang,et al.  How Good is Your Controller? Application of Control Loop Performance Assessment Techniques to MIMO Processes , 1996 .