Research On Risk Management System Of Nuclear Power Plant DCS Software Projects

Digital Instrument and Control System(DCS)is majorly used for monitoring and controlling the operation status of Nuclear Power Plants(NPP),it is critical for ensuring that NPPs can operate safely and stable.In recent years,with the development of related technologies,involving DCS becomes one important feature of advanced nuclear reactor.DCS can help to greatly improve nuclear systems’ reliably and stability,reduce the negative impact of human errors,increase the fault detecting capability.Software plays an important role in NPP’s DCS,it is treated as very complex engineering practice.The risk management of DCS’s software has huge impact on the results of the whole project.To ensure the quality of final offerings and deliverables,we must analysis,assess and control the risk of NPP DCS’ software project correctly,then the effective and suitable risk control plan can be conducted.There is urgent need to develop a risk management system which can fulfil the special requirements of NPP DCS software projects.In China,NPP DCS software engineering is still in early phase,there is no unified DCS software risk analysis,forecast or assess standards.To solve this issue,in this thesis,a new method of risk management of NPP DCS software project has been proposed.During the risk identification phase,based on pre-defined classification,a new and more comprehensive way is used to get the risk list of a certain NPP DCS project;during the risk assessment,a new assessment system that combined the advantages of risk matrix,Back-propagation(BP)Neural Net optimized by Genetic Algorithm(GA),and the knowledge and experience of industry professions,has been proposed,in order to estimate and forecast the risks in the project.By applying this new system,the risk assessments become more comprehensive,objective,and effective.The risks have been prioritized based on mean partition,then in a certain NPP DCS project,the risks can be handled and controlled via different strategy according to different priorities.In this thesis,the requirements of NPP DCS project risk management have been analyzed,the requirement analysis of risk identification,risk evaluation,risk mitigation,risk monitor and control have been provided.Regarding system design,the risk management system’s framework has been built,and the risk evaluation model based on GA optimized BP neural net has been developed,tested,simulated and analyzed.For system implementation,this thesis has provided the implementation method of this system’s critical modules,such as risk identification,risk evaluation,risk mitigation,risk monitor and control,and general management.The system proposed in this thesis has been applied to practice in an actual NPP DCS software project’s risk management,plenty of test cases have been provided and tested.It has been proved helpful for nuclear software engineers,project managers and other stakeholders,it can provide a new thought of risk management.By using this GA improved BP neural net mode,the risks with high priority and huge negative impact on project can be dig out.It also helps to improve the effectiveness of NPP DCS software projects’ risk management,thus improve the quality of NPP DCS software.