Fast Time Scale Simulation of a Reactor Control System

The setup and results of a reactor kinetics and servo-system simulation is presented. The reactor, a 50-megawatt high flux materials and engineering test reactor designated Belgian Reactor-2, is controlled by means of a saturating servomechanism actuating a cadmium containing regulating rod. The simulation was set up on a 100/1 time scale using GAP/R high-speed analog computing equipment, and solutions were presented repetitively. Represented in the setup were six delayed neutron groups, variations in regulating rod effectiveness with displacement and reactor cycle time, four quadrant servomotor torque-speed characteristics, control rod position limiting, and a temperature coefficient of reactivity. The results presented include the response of the system to: reactivity disturbances, changes in desired power set point, increase of power on a constant period, and transition from manual to automatic control during startup.