A multi-variable disturbance observer for model predictive control

In this paper, a new method for disturbance rejection suitable for dynamic matrix control (DMC) is proposed. DMC has been widely used in many practical engineering fields as a very useful control method. Despite its usefulness and achievements, it has been pointed out that DMC gives poor performance with respect to disturbance rejection for some kinds of disturbances such as ramp-like disturbances. To overcome this weakness, we developed an easy-to-implement disturbance observer, which only requires step response models of plants. Illustrative examples are provided to show its effectiveness for the case where a ramp-like disturbance is acting on a plant.