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A New Uncertainty-Based Control Scheme of the Small Modular Dual Fluid Reactor and Its Optimization

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The small modular dual fluid reactor is a novel variant of the Generation IV molten salt reactor and liquid metal fast reactor. In the primary circuit, molten salt or liquid eutectic metal (U-Pu-Cr) is employed as fuel, and liquid lead works as the coolant in the secondary circuit. To design the control system of such an advanced reactor, the uncertainties of the employed computer model and the physicochemical properties of the materials must be considered. In this paper, a one-dimensional model of a core is established based on the equivalent parameters achieved via the coupled three-dimensional model, taking into account delayed neutron precursor drifting, and a power control system is developed. The performance of the designed controllers is assessed, taking into account the model and property uncertainties. The achieved results show that the designed control system is able to maintain the stability of the system and regulate the power as expected. Among the considered uncertain parameters, the reactivity coefficients of fuel temperature have the largest influence on the performance of the control system. The most optimized configuration of the control system is delivered based on the characteristics of uncertainty propagation by using the particle swarm optimization method.
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... Liu et al. presented a small modular dual fluid reactor as a novel variant of the Generation IV molten salt reactor and the liquid metal fast reactor [13]. In the primary circuit, molten salt, or the liquid eutectic metal (U-Pu-Cr), is used as fuel, and liquid lead works as the coolant in the secondary circuit. ...
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