Candu® NPP reactor regulating system modelling using CATHENA

A CATHENA model is developedfor the reactor regulating system and tested independently. Then, a complete CATHENA model is created by combining this model with the reference CATHENA model which has been developed to analyze a loss-of-coolant accident (LOCA) for Wolsong 2 generating station. This model is intended to set up plant control routines in CATHENA to provide a trip coverage analysis capability. The purpose of this work is to model the reactor regulating system using the CATHENA control model system. It includes the demand power routine, the light water zone control absorbers, mechanical control absorbers and adjusters. The CATHENA model was tested for steady state at 103% full power. A postulated accident transient (small LOeA) was also tested. The results show that the control routines in CATHENA were set up properly.