Unveiling the Vulnerabilities of Observer-Based Attack Detection in Cyber-Physical Microgrids

Microgrids nowadays are heavily dependent on communication technologies for optimal functionality, yet this dependence leaves them vulnerable to cyber-attacks. Such attacks may compromise the voltage stability, disrupt coordination among grid components, and result in undesirable damages. Model-based attack detection methods using observers have been the promising approach for identifying cyber-attacks on microgrids. This letter, however, reveals that stealthy attacks can be specifically designed to completely bypass these observer-based detection methods. By examining the unknown input observer (UIO), Luenberger observer (LO), and sliding mode observer (SMO) as case studies, the letter highlights the limitations these observers encounter when attempting to detect such sophisticated attacks, highlighting a critical gap in current cyber-defense mechanisms in microgrids.