RNGA based control system configuration for multivariable processes

This paper presents a new control-loop configuration criterion for multivariable processes. Both the steady-state and transient information of the process transfer function are investigated. A new interaction measurement, relative normalized gain array, is proposed for evaluating control-loop interactions. Consequently, a new loop pairing criterion based on the relative normalized gain array is proposed for control structure configuration. The main contribution of this work is that it systematically analyzed the process transferring characteristics from both steady-state and transient perspectives and derived a feasible solution for the problem. Several examples, for which the conventional relative gain array based loop pairing criterion gives an inaccurate interaction assessment, are employed to demonstrate the effectiveness of the proposed interaction measure and loop pairing criterion. (C) 2009 Elsevier Ltd. All rights reserved.