Dynamic model for the control system simulation and design of a 200 MW nuclear heating reactor

The paper develops a nonlinear dynamc model used in a wide range control system simulation for a 200 MW Nuclear Heating Reactor (NHR 200). Besides a one point neutron kinetics equation and terrperature feedback based on the lumped fuel and coolant terrperature, which are the usual methods used in modeling of PWR, two other factors are also considered in order to suit the wide range operation. The first consideration is the natural circulation in the primary loop because it affects the heat transfer coefficients in the core and in the primary heat exchanger (PHE). The second consderation is the flow rate variation in the secondary loop which leads to some nonlinear properties. The simulation results show that the model is accurate enough for control system simulation. Some model reduction basis can be obtained through the dynamic analysis