Observer aided robust control for cyber physical power grids with event triggered sliding mode controller

Abstract

The growing integration of renewable energy in both islanded and interconnected microgrids has rendered Cyber-physical stability and resilience a vital area of research. Conventional controllers, including PID and linear state-feedback, are susceptible to network-induced delays, denial-of-service (DoS) attacks, and false data injection, resulting in diminished reactive power support and the risk of voltage collapse. This paper proposes an Observer-Aided Robust Control Framework that integrates an Event-Triggered Sliding Mode Controller (ET-SMC) with improved anomaly detection to address these challenges. An Extended Kalman Filter (EKF) and Sliding Mode Observer (SMO) are formulated to estimate hidden state variables and identify malicious data alterations with high sensitivity, facilitating dependable control decisions in the presence of Cyber-attacks. The performance of anti-windup PID and baseline SMC is evaluated against ET-SMC with observer augmentation, demonstrating that the proposed strategy offers enhanced robustness, quicker transient response, and diminished chattering. A stability-guaranteed Event-triggered communication protocol is developed through Lyapunov analysis to reduce bandwidth consumption while maintaining voltage and reactive power regulation. The proposed framework is validated on a real-time OPAL-RT hardware-in-the-loop (HIL) microgrid testbed, demonstrating its effectiveness in scenarios involving renewable intermittency, communication noise, and coordinated Cyber-attacks. Comparative results demonstrate that ROC-based detection performance and time-domain simulations underscore the advantages of observer-aided ET-SMC in ensuring resilient, low-bandwidth, and real-time Cyber-physical control for next-generation power grids.