Detecting Stealthy Attacks in Power Systems based on Switching and Zonotopes

This paper mainly focuses on the problem of detecting stealthy attacks in power systems with unknown-but-bounded (UBB) disturbances and noises based on switching and zonotopes. A switching-based moving target defense (MTD) strategy, which is characterized by the average dwell time (ADT) property, is presented in order to enhance the uncertainty of the power system. In addition, sufficient conditions are given for the switched power system to be robust with the degree of
$H$
disturbance attenuation. The impact of MTD strategy on stealthy assaults is then analyzed in two scenarios, in which the adversary can attack either all measurement output channels or a subset of them. Meanwhile, a novel detector based on MTD and zonotopes is designed to detect stealthy attacks for the switched power system. Finally, a three-generator and six-load-bus power system is provided to illustrate the effectiveness of the main results.