A Secure Control Design for Networked Control Systems with Linear Dynamics under a Time-Delay Switch Attack

Abstract

Networked control systems (NCSs) are designed to control and monitor large-scale and complex systems remotely. The communication connectivity in an NCS allows agents to quickly communicate with each other to respond to abrupt changes in the system quickly, thus reducing complexity and increasing efficiency. Despite all these advantages, NCSs are vulnerable to cyberattacks. Injecting cyberattacks, such as a time-delay switch (TDS) attack, into communication channels has the potential to make NCSs inefficient or even unstable. This paper presents a Lyapunov-based approach to detecting and estimating TDS attacks in real time. A secure control strategy is designed to mitigate the effects of TDS attacks in real time. The stability of the secure control system is investigated using the Lyapunov theory. The proposed TDS attack estimator’s performance and secure control strategy are evaluated in simulations and a hardware-in-the-loop environment.

An Improved Model Predictive Fast Frequency Control for Power System Stability Against Unknown Time-Delay Switch Attack

“…To minimize the steady-state error, an integrator can be embedded in (1), and an auxiliary variable is introduced as…”

“…A Modern power grid, taking advantages of advanced control strategies, cost-competitive technologies and information and communication technology (ICT), is a cyberphysical systems (CPSs), which are vulnerable to cyber attacks. Some of the well-known cyber-attacks are denial of service, which disables access to the system information or a service, false data injection, which intentionally manipulates the exchange of data, replay attack, which maliciously repeats valid data transmission [1]. A recently found attack, the time-delay switch attack (TDSA) [2], is made by inserting time delays into communication channels of CPSs.…”

“…However, this method is only able to estimate constant time-delay and requires a large set of data for training. Moreover, as pointed out in [1], the NNbased methods are prone to maliciously altering the training data and cause disastrous operation and system instability. The sliding mode-based TDE was first developed by [24] to estimate the unknown, fast time-varying and random timedelay.…”

Resilient Networked Control of Inverter-Based Microgrids against False Data Injections

“…Since the secondary control heavily relies on communications and cyber infrastructures in a closed control loop, it can be labeled as a networked control system [3]. Similar to all networked control systems, the secondary control of microgrids is vulnerable to cyber threats.…”

“…The DoS targets the availability of machines or networks to temporarily or indefinitely distort the service to its intended users. The FDI manipulates the data exchanges throughout the network, which misleads the control center and disturbs the system operation [3,4].…”