Optimal control of reliability failure risk contagion dynamics in nuclear power systems

Risks originating from technology, management, and the external environment are a concern during the operation of nuclear power systems. The spread of these risks can impact the safe operation of nuclear power, especially when a component failure accelerates the risk impact, potentially leading to accidents and disasters. This paper develops a risk contagion dynamics model for nuclear power systems using epidemic dynamics mechanisms. The risk contagion coefficient due to reliability failure is utilized to adjust the reliability degradation equation. The SEIQRS model and Hamiltonian equation for nuclear power reliability risk contagion dynamics are reconstructed by introducing maintenance strategies like preventive maintenance, isolation maintenance, and defect maintenance. Optimal control methods are applied to mitigate the impact of reliability risk. Using a nuclear power plant operation system as an example shows how reliability failures amplify risks. Implementing maintenance strategies enhances reliability while reducing failures. Comparative analysis results underscore the effectiveness of addressing risk contagion impact through reliability degradation failure, thereby improving the reliability risk dynamic mechanism of nuclear power. The optimal maintenance strategy significantly boosts the reliability of nuclear power systems while mitigating the risk of contagion, providing valuable insights for optimal decision-making in nuclear power safety management.