Fixed-Time Fault-Tolerant Consensus of MASs Against Power Faults via Multi-Signal Quantization and Fuzzy Graph With Application to DC Microgrid

The practical fixed-time quantized fault-tolerant control of multi-agent systems (MASs) under power faults and fuzzy graphs is addressed in this article. Firstly, a state-dependent fuzzy graph is introduced to describe information exchange between agents. Specifically, the topology weight is considered as an unknown state-dependent function, which is more practical than the common fixed topology. Secondly, the novel actuator and sensor power faults are proposed in this paper. Unlike gain and bias faults, power faults cause the input powers of sensors and actuators to become unknown time-varying functions. The impact of power faults is handled by designing compensation signals. In addition, the state constraints are realized by conducting coordinate transformations, thereby ensuring the system’s safety. To reduce resource depletion, this article employs a quantizer to quantize all states and inputs, and designs the needed controller based on the discontinuous quantized states. The relationship between quantized signals and unquantized signals is established to compensate for the discontinuity caused by quantization. Under the developed quantized controller, the boundedness of all closed-loop signals and the practical fixed-time stability of the system can be guaranteed. Finally, the feasibility of the proposed control strategy is validated by simulating an actual circuit system.