Fuzzy logic-based power control system of a supercritical-pressure light water fast reactor

Supercritical-pressure light water fast reactor is one of the current concepts of the Generation IV reactors which have significant improvement on the efficiency, safety and economy. A change of power to flow ratio leads to a change of the outlet coolant temperature in second. The temperature deviation must be suppressed as small as possible to keep the integrity of the reactor structures, like the reactor outlet nozzles, main steam line, etc. The plant dynamics analysis was carried out by giving perturbations of power to flow ratio, and then its influence on the reactor power and outlet coolant temperature were observed. A fuzzy logic-based power control system was designed and applied to the plant to compensate the effects of the perturbations. The control's parameters, like the member functions of fuzzification were optimized to satisfy the criteria of allowable outlet coolant temperature deviation and stability. The power could be controlled stably by the optimized control design and the criterion of the outlet coolant temperature deviation is satisfied against perturbations of power to flow ratio.