Improved Proportional-Integral Observer-Based Fault-Tolerant Control for MASs Against Unbounded FDIA

An improved proportional-integral observer (PIO) based fault-tolerant control problem is addressed for multi-agent systems (MASs) with disturbance under unbounded false data injection attack (FDIA) over an undirected graph. The FDIAs are modeled as a class of unbounded attack signals. Notably, an augmented descriptor system is formulated by letting the FDIA be an auxiliary state vector. Then, an improved PIO is constructed to achieve the estimation of process faults and FDIA simultaneously. A compensation term is incorporated into the PIO to attenuate the effects of external disturbances and thus improving the accuracy of the PIO. Besides, an improved PIO-based fault-tolerant secure control scheme against unbounded FDIA is developed to achieve consensus even in the presence of process faults. Finally, the effectiveness and advantages of the proposed control strategy is verified through a simulation result.