HANDLING DISTURBANCES OF THE SCAN PERIOD IN DISCRETE LQG CONTROL SYSTEMS

Abstract

Computer-based control applications, especially if they run under general-purpose operating systems, often exhibit variance of the scan period of processing inputs and outputs. Although this phenomenon is usually neglected when discrete control algorithms are used, in some cases it can cause significantly worse performance of the control loop. In the paper a modified discrete LQG control algorithm that takes disturbances of the scan period into account is proposed. It is also shown that such a controller can be implemented even on relatively simple hardware platforms.