Nonfragile Fault-Tolerant Control for Power Cyber-Physical Systems With Cyber Attacks.

Area of Science:

• Control Systems Engineering
• Cybersecurity
• Power Systems

Background:

• Power cyber-physical systems (CPSs) are vulnerable to sophisticated denial-of-service (DoS) attacks.
• Actuator failures and controller gain perturbations can compromise system stability.
• Concealed cyber attacks require advanced analysis techniques.

Purpose of the Study:

• To develop a nonfragile fault-tolerant control strategy for power CPSs under concealed DoS attacks.
• To analyze DoS attacks using a double-layer stochastic process, specifically a hidden semi-Markov chain.
• To ensure the mean-square stability of the closed-loop system.

Main Methods:

• A double-layer stochastic process combining a semi-Markov chain and observed modes to model DoS attacks.
• An observed-mode-dependent nonfragile control scheme accounting for actuator failures and controller perturbations.
• A mode-dependent Lyapunov function and the semi-Markov kernel (SMK) approach to derive stability conditions.

Main Results:

• Sufficient conditions for mean-square stability of the closed-loop power CPS were derived.
• The proposed control scheme effectively handles stochastic dwell time distributions under incomplete attack information.
• Simulation results validated the effectiveness of the developed nonfragile fault-tolerant control approach.

Conclusions:

• The novel stochastic framework provides robust fault-tolerant control for power CPSs facing concealed DoS attacks.
• The semi-Markov kernel approach systematically addresses uncertainties in attack modes and dwell times.
• The research contributes to enhancing the security and reliability of power systems in adversarial environments.