Encrypted Networked Control with Quantization and Event-Triggered Mechanism
DOI:
https://doi.org/10.5890/JAND.2026.06.015Abstract
This paper addresses the security and resource efficiency challenges in networked control systems (NCSs)—specifically, the integer-only operation limitation of homomorphic encryption (HE), ciphertext expansion-induced communication overload, quantization nonlinearities that degrade stability or limit convergence, and the lack of a unified solution integrating security and efficiency. To resolve these issues, a unified encrypted control framework is proposed. For HE's integer constraint, static quantization is designed for control gains and dynamic quantization for system states (adjusting sensitivity by state magnitude to ensure asymptotic convergence of quantized states to equilibrium, overcoming fixed-sensitivity quantizers' bounded stability limitation). Different from traditional encryption control, a quantization-aware dynamic event-triggered mechanism (DETM) is developed to reduce communication load and relieve ciphertext expansion, incorporating quantization-related errors into its triggering condition to transmit encrypted data only when necessary and guarantee Zeno-free operation. Finally, simulation results further prove the proposed method is effective.References
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