Networked microgrids, which integrate distributed energy resources like solar inverters and battery systems, face growing cybersecurity threats. Attackers can exploit two attack vectors simultaneously: hijacking remote control systems to send false reference signals to DERs, and corrupting voltage and current sensor readings through electromagnetic interference or direct spoofing. Existing defenses address these problems separately—physical shields for sensors or cyber algorithms for detection—but lack coordinated, system-wide protection at reasonable cost.
Researchers have now proposed a multi-layer defense strategy that coordinates physical and cyber defenses across the entire microgrid. Rather than defending every sensor with expensive shielding, the framework deploys physical protection only at critical points: the local points of common coupling where microgrids connect to the wider network. These secured sensors provide trusted baseline data for the rest of the system.
The cyber layer then uses this trusted data to detect spoofing attacks on DER-level sensors through a proactive scheme. The system deliberately introduces small parameter perturbations—controlled disturbances in voltage or current setpoints—to observe how the network responds. Sophisticated sensor spoofing attacks, which mimic normal conditions, become detectable because their responses deviate from expected physics.
Once an attack is confirmed, coordinated mitigation algorithms across the microgrid and individual DERs work together to estimate sensor biases and correct readings in real time. Laboratory tests on a cyber-physical testbed demonstrated the framework's effectiveness against diverse attack scenarios, including gradual and sudden sensor corruption.
This hierarchical approach balances security, cost, and performance by concentrating physical defenses where they matter most while leveraging distributed cyber intelligence. For utilities deploying networked microgrids, it offers a practical pathway to detect and tolerate sensor attacks without the expense of hardening every connection point.
