Cable Insulation Failure Probability Analysis in Nuclear Power Plant Distribution Cabinet Fire

This paper takes the nuclear power plant power distribution cabinet fire as example and adopts FPRA methodology to analyse the failure probability of cable insulation at contiguous region among distribution cabinet. The influential factor that fire brigade dealt with the fire in the spot is considered in this research. The cumulative distribution function of fire brigade's arriving and extinguishing time is conducted discretization, confirming the sample statistics of areas and establishing the numbers of cable insulation failure events of distribution cabinet fire. Combining failure predicted model of cable insulation and calculating the failure situation of cable insulation under each of fire background, obtaining the probability that cable insulation failure events among the distribution cabinet fires. The results show that the HRRmax of distribution cabinet fire in term of case scenario is 750 kW, the cable never happens the insulation failure; when the distribution cabinet fire is 1000 kW, the possibility of cable insulation failure is 12.6%.