Research On CPR1000 Accident Mitigation Strategies And Human Error Prevention Intelligent Operation And Maintenance System

The analysis and mitigation of severe accidents in the Nuclear Power Plants(NPPs)has become a research focus of general interest and concern in the nuclear energy industry since the Fukushima nuclear accident.In order to improve the safety of NPPs,a massive verification work of depressurization and water injection strategies in Severe Accident Management Guidelines(SAMGs)has been carried out by researchers all over the world.But the phenomena of compound accidents,such as the station blackout along with small break loss-of-coolant accident,are much more complex,so it is necessary to carry out further simulation and verification.On the other hand,the success of the implementation of severe accident mitigation strategies to a great extent depends on human reliability.Previous severe accidents have also shown that human error is a key factor to the safety of NPPs,so how to effectively prevent human error has also become an emphasis in NPPs management.In this paper,taking the station blackout along with small break loss-of-coolant accident of CPR1000 as the basic accident sequence,the sensitivity of external water injection strategies of the primary system is analyzed using a severe accident analysis code.First of all,the phenomena of basic accident sequence and process are described in detail,then the sensitivity analysis of depressurization strategies of the primary system before external water injecting has been completed to find out the optimum depressurization strategies for different cases.Secondly,based on the optimal depressurization strategies,the effects of different external water injection time and different flow rates on accident mitigation are analyzed.Finally,more optimized external water injection strategies are proposed to improve the efficiency of severe accident mitigation.The research result can provide a reference for the improvement of CPR1000 NPPs’ SAMGs and training courses of similar NPPs sequences.On the other hand,in order to further reduce the risk of human error in NPPs accident mitigation measures,the Mixed Reality technology is applied to NPPs,and an intelligent operation and maintenance system of NPPs with guidance and training functions is developed using Microsoft HoloLens.With the guidance of Human Factor Engineering(HFE),the NPPs electric valve is selected as the initial research object based on user requirement analysis.According to the functional demands,the electric valve operation and maintenance system is designed and developed with relevant software such as Unity3D and Visual Studio.Finally,the system is quantitatively evaluated by means of human reliability analysis.The results show that the intelligent operation and maintenance system can effectively reduce the change of human error in daily operation and maintenance,and can help to reduce the risk of human error in NPPs accident mitigation measures.