GEOMETRIC INTERPRETATION AND MEASURES OF DYNAMIC INTERACTIONS IN MULTIVARIABLE CONTROL-SYSTEMS

A technique is developed to evaluate the interactions of a multivariable control system. The technique can be employed to select the best pairing configuration of the control system, but more than that, it is capable of providing guidelines for controller design. The technique arises from a geometric analysis of the stability boundaries in the proportional gain space. As a result, the relative gain array (RGA) is given a geometric interpretation and demonstrated to be a convenient steady-state interaction measure. A convenient dynamic counterpart is then quantified to predict dynamic interactions based on simple response experiments. The validity of the proposed dynamic interaction measures is verified by numerous literature examples.