Modal Control of a Nuclear Power Reactor

Abstract The control scheme developed is based on a nonlinear axial model of the reactor using the diffusion theory of neutrons. The model is valid for a time period in which the reactor changes from one power level to another. The controlled variable is the axial distribution of the neutron density; the control variables are the positions of several partly or fully absorbing (generating) control rods. The control scheme is desiσned to control the eigenfunctions of the reactor. It is able to control the total power as well as the axial power distribution in the core of the reactor. Because the controller is developed using the nonlinear system equations, it is independent of the operating power level of the reactor. Furthermore the control scheme is very simple and relatively insensitive to parameter changes of the plant, so that it is well suited for practical use.