Research on KDA System Reliability Model Based on Total Probability Formula

摘要

With the rapid development of computer technology, automation and control technology is more and more widely used in all aspects of life. Severe accident instrument control system as an important defense to ensure nuclear power plant safety after the serious accident, its usability and reliability is vital. However, the traditional fault tree analysis method is faced with complicated and repeated combing problem. Therefore how to accurately assess the reliability of the system has become the focus of systematic analysis and research. In order to solve this problem, this paper analyzes the instrument control system in severe nuclear accident, decomposes the complex control system by using the system flow chart, builds the reliability calculation model based on the total probability formula, and proposes a new method to evaluate the reliability of the control system. In addition, the model can add or delete modules to suit different needs, and can be adjusted according to other control links or control systems to make it more scalable. Finally, the model is software simulation verification and the result is in line with the index, which proves that the method of this model is suitable for KDA and related system. It has great reference value for complex automatic control system and can be popularized in different control systems of nuclear instrumentation industry.