SAFETY SYSTEM IMPROVEMENT FOR THE NEXT GENERATION BWR

摘要

The studies aiming at the establishment of a plant conceptfor a Boiling Water Reactor (BWR) of the next century, werestarted in 1990 as a series of joint research by Japanese BWRutilities and NSSS vendors. During phase II of this program, areference plant concept was developed (Kubokoya, et al., 1995;Kinoshita, et al., 1996)] to meet the requirements provided byJapanese utilities. The investigation related to the safetysystems in phase III of this study, focuses on severe accident(SA) capability and some deregulation of conventional designapproaches in order to pursue further economy.The safety systems of the current reference plant concepthave the following features; provision for sufficient graceperiod, probabilistic safety assessment (PSA) and SAconsideration from the design stage, appropriate combinationof active and passive systems to enhance safety, and bettereconomy. This paper describes these improved safety systemfeatures, and discusses the impact on plant performance andeconomy.