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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.
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An Observer-Based Control for a Networked Control of Permanent Magnet Linear Motors under a False-Data-Injection Attack
In a centralized Networked Control System (NCS), agents share local data with the central processing unit that generates control commands for agents. The control center in an NCS receives information from the agents through a communication network and produces control commands for agents. Despite all of the advantages of an NCS, such as reduced design cost and simplicity, the integration of networked connectivity can expose the NCS to adversarial attacks, such as false data injection (FDI). In this paper, a novel control approach will be developed to mitigate the FDI attack’s effect and guarantee the control objective in a networked system of permanent magnet linear motors. To achieve this, a non-singular terminal sliding mode control will be designed using an observer to ensure the tracking objective. The extended state observer will estimate the state of the system and estimate the FDI attack in real time. The control center will produce a control signal which is robust to the FDI attack and any disturbance. A Lyapunov-based stability analysis will be used to prove the stability of the observer-based controller. A three-agent permanent magnet linear motor network is selected for the simulation to show the effectiveness of the proposed scheme.
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- Award ID(s):
- 2241718
- PAR ID:
- 10487539
- Publisher / Repository:
- IEEE
- Date Published:
- ISBN:
- 979-8-3503-8211-2
- Page Range / eLocation ID:
- 1 to 8
- Format(s):
- Medium: X
- Location:
- Tampa, FL, USA
- Sponsoring Org:
- National Science Foundation
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