Deterministic Network Calculus-Based H∞ Load Frequency Control of Multiarea Power Systems Under Malicious DoS Attacks

In multiarea power systems, by preempting the transmission resources, denial-of-service (DoS) attacks may cause continuous packet losses in communication network and correspondingly make a performance degradation or even instability of the load frequency control (LFC) system. In this paper, a LFC scheme resilient to DoS attacks is developed. First, the dynamic boundary behaviors of data flow transmitted among multiple switches in normal no-DoS attack scenarios are described by using deterministic network calculus. Then, the analytic relationships among the upper transmission delay bound and key network parameters (e.g., packet size, forwarding rate, and hops) are deduced. Second, considering that the influences of bounded transmission delays on control instructions, the dynamics of closed-loop LFC systems are described as a series of subsystems with actual delays as the jumping decision variables. The established jumping model clearly demonstrates the dynamic evolution process of LFC systems under DoS attacks and stochastic delays. The H-infinity-stabilization criteria considering parameter uncertainties are further deduced by using the Lyapunov theory and a constrained optimization algorithm is developed. Finally, case studies show the effectiveness of the proposed method.