THE INTEGRATE METHOLD OF THE LIVING PSA MODEL AND THE RISK MONITEOR MODEL

Abstract

At present, the usual practice of Chinese nuclear power plants is to maintain the Living PSA model and the Risk Monitor model as two independent models. This paper summarizes a set of methods, which can integrate the average model and the instantaneous model into one RISKSPECTRUM file (*.rpp) based on the practical experience of Qinshan NPP (Nuclear Power Plant).

The method can facilitate and simplify the long term maintenance workload of the PSA model. The main points are as the following:

1)The fault tree is used as the input of initiating event of the event tree to process the frequency value corresponding to each Plant Operating State (POS).

2)The method of preprocessing event tree is used to deal with the lumped initiating event, which can well reduce the number of split event trees.

3)Based on the above 1) and 2), two sets of Boundary Condition are used to enable that one RISKSPECTRUM file (*.rpp) can get both RM instantaneous CDF and Living PSA average CDF.