Communication-free fault-tolerant control of distributed DC microgrid against sensor faults

TL;DR

This paper introduces a communication-free control system for DC microgrids that can handle sensor faults in real time, improving reliability and security.

Contribution

A novel real-time fault-tolerant control framework using a single observer and decentralized control without communication.

Findings

The proposed framework successfully reconstructs sensor faults using a PI-UIO.

Decentralized PBC and consensus-based current sharing enhance system resilience and scalability.

Simulation results show the framework outperforms recent methods in fault tolerance.

Abstract

DC Microgrids are becoming increasingly popular for their efficiency and suitability for integrating renewable energy source and energy storage systems. However, unexpected sensor faults can severely compromise voltage regulation, current sharing, and overall system stability, posing a risk, especially for critical applications. Existing resilient control schemes for DC Microgrids often relies on hardware redundancy, multiple observers, or communication-based fault mitigation, leading to slow fault mitigation, increased cost, complexity, and vulnerability to cyber threat. To address the limitations of existing methods this paper proposes real-time reconfiguration framework to tolerate adverse sensor faults in islanded DC Microgrids. The proposed scheme leverages a single Proportional Integral Unknown Input Observer (PI-UIO) to reconstruct sensor faults and reconfigure a decentralized Passivity Based Control (PBC) at the primary level and a distributed consensus based current sharing controller at the secondary level. Unlike conventional methods, the proposed scheme operates autonomously without communication, thus enhancing the scalability, reliability and resilience against cyberattacks. Moreover, the design of the PI-UIO and PBC is achieved with decentralized parameters to enable seamless plug-and-play integration. Extensive simulation and real time simulation results validate the effectiveness and superiority of the proposed FTC framework compared with the recent methods.

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