Fault-Tolerant, Distributed Control for Emerging, VSC-Based, Islanded Microgrids—An Approach Based on Simultaneous Passive Fault Detection

Abstract

This paper proposes a fault-tolerant control and a robust, distributed, simultaneous, passive fault detection and isolation (or FDI) for islanded ac microgrids (MGs), including heterogeneous distributed generations and battery energy storage systems (BESSs). Disturbances and both actuator and sensor faults are considered in this paper to design a robust distributed control. The nature of the considered faults is general to deal with any sources, e.g., cyber threats (in the form of data integrity attacks) and sensor issues. In this regard, a mixed $H_\infty / H_{-}$ formulation is introduced in order to detect and eliminate the undesirable effects of the aforementioned defected components simultaneously, thereby achieving robust performance. Besides, sufficient conditions based on extended linear matrix inequality (also known as LMI) are outlined. Voltage and frequency regulation, active power-sharing, and the state of charge balance of BESSs under faulty conditions are investigated. Different scenarios are tested on a detailed model of a test MG system. The effectiveness of the proposed scheme on mitigating the impacts of faults and disturbances on the distributed energy resources’ (DERs’) performance is evaluated through comprehensive and comparative simulations based on MATLAB/Simulink. Moreover, experimental studies are conducted in order to validate the results in the corresponding practical scenarios.

Keywords

• Distributed control
• fault-tolerant
• fault detection and isolation
• linear matrix inequality
• islanded microgrid
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