Covert Attack Detection and Reliability Analysis of PWR Pressurizer Pressure Control System Based on Q-Chaos TH/FH Signals

Covert attacks can gradually destroy the pressure regulation function of the pressurized water reactor (PWR) pressurizer, thus seriously threatening the safe operation of nuclear power plants. However, since convert attack has the ability of launching an attack without changing the residuals, some traditional attack detection methods lose their effects. To address this problem, a detection method is proposed based on quantum-chaos time/frequency hopping (Q-chaos TH/FH) signals. The proposed method is based on chaotic systems’ randomness and initial value sensitivity properties and adopts a quantum random sequence as the initial value of chaotic systems. In this way, a Q-chaos TH/FH-based detection signals with two-dimensional stochastic properties of duration and frequency are designed. Further, modulation and demodulation algorithms are designed to prevent attackers from accessing sensitive information and launching attacks. In addition, the frequency hopping rate constraint that maintains the system’s stability is derived through theoretical analysis. This constraint ensures the system maintains stable control performance in both frequency hopping rate synchronous and transient asynchronous states. Finally, hardware-in-the-loop simulation experiments are conducted to verify the effectiveness of the proposed method.