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This work focuses on the problem of enhancing cyberattack detection capabilities in process control systems subject to multiplicative cyberattacks. First, the relationship between closed-loop stability and attack detectability with respect to a class of residual-based detection schemes is rigorously analyzed. The results are used to identify a set of controller parameters (called "attack-sensitive" controller parameters) under which an attack can destabilize the closed-loop system. The selection of attack-sensitive controller parameters can enhance the ability to detect attacks, but can also degrade the performance of the attack-free closed-loop system. To balance this trade-off, a novel active attack detection methodology employing controller parameter switching between the nominal controller parameters (chosen on the basis of standard control design criteria) and the attack-sensitive controller parameters, is developed. The proposed methodology is applied to a chemical process example to demonstrate its ability to detect multiplicative sensor-controller communication link attacks.
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Cyberattack detectability-based controller screening: Application to a nonlinear process
In this work, multiplicative cyberattacks targeting the sensor-controller communication link of a process control system are considered. The interdependence of detectability of an attack with respect to a general class of residual-based detection schemes and the control parameters is characterized. Exploiting this dependence, a controller screening methodology that may be used to incorporate cyberattack detectability into the standard controller design criteria is presented. Using a chemical process example, the application of the controller design screening to a nonlinear process is demonstrated.
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- Award ID(s):
- 2137281
- PAR ID:
- 10416922
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- 14th International Symposium on Process Systems Engineering
- Volume:
- 49
- Page Range / eLocation ID:
- 1453 - 1458
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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