SPATIAL CONTROL OF A LARGE PRESSURIZED HEAVY-WATER REACTOR

The paper presents the design of a near optimal linear regulator for c ontrolling xenon-induced spatial oscillations in a large, pressurized heavy water reactor. The nonlinear mathematical model of the reactor i ncluding xenon iodine dynamics is characterized by 56 state variables and 14 inputs, This nonlinear model is Linearized over rated power of the reactor and then the singularly perturbed structure of the linear model is exploited to decompose it into a fast subsystem of 14th order and a slow subsystem of 42nd order. The slow subsystem regulator prob lem is formulated as a cheap control problem that entails the solving of regulator problems of a 28th-order submodel and a 14th-order submod el, The fast subsystem regulator problem is also solved, Separately de signed regulators are finally combined to obtain the near-optimal comp osite control for the original 56th-order model.