Research on the passive safety system design during ACP100+

ACP100+ was developed Based on ACP100 which is aimed to enhance the safety further. Inner PRZ and small steel containment design was adopted. The strategy of the emergency core cooling, pressure controlling in the containment and long-term cooling during LOCA are proposed. According to the elementary calculation and analysis, the accumulators can be cancelled for the ACP100+ and the safety injection system gets simpler. The release of mass and energy can be controlled more easily due to the smaller size of break based on pressure restrained pool and containment pool above the small steel containment. Meanwhile the long-term residual heat can the taken out through the pool above the containment based on the natural convection and the inherent safety can be enhanced more. (author)