Optimal Control of Xenon Oscillations in Load Follow of Large Nuclear Reactors

Abstract

Abstract The problem of xenon spatial oscillations control during the load follow of large pressure water reactors is formulated as an optimization problem. The state equations of the system are composed of the one-group diffusion equation with temperature and xenon feedbacks, the iodine-xenon dynamics equations, and an energy balance equation for the core. The resulting distributed parameter model is first coverted into a lumped one by eigenfunction expansion and then a combination method, based on Differential Dynamic Programming and Matrix Riccati Method, is developed to obtain the optimal solution which can closely follow the desired power demand and maintain the desired flux distribution without too much control effort. Computational results show that the algorithms used in the proposed method converge for a broad spectrum of load follows. With the same precision, the combination method, comparing with DDP alone, is fairly computationally efficient.