Design of an Output Feedback Pressurizer Controller With a Decoupling Precompensator for PWRs

Abstract

The pressurizer is a crucial component for the safe operation of pressurized water reactors (PWRs). The pressure and level control systems of the pressurizer interact strongly with each other. This cross-coupling between the inputs and outputs makes it difficult for conventional control methods to achieve optimal control effects on both the pressure and level. A simple state feedback control for the pressurizer with a decoupling pressure level precompensator realized using the diagonal matrix method is therefore proposed in this study. A detailed three-zone nonequilibrium dynamic model that reflects the stratification and mass and energy exchange phenomena inside the pressurizer is applied, and a state feedback control that utilizes the physically measurable states of the pressurizer is employed to simplify the state feedback controller to a form that is equivalent to the output feedback control. The improvement of the existing dominant pole placement technique in the feedback controller is described, and the correlation between the parameters and automated tuning methods is also given. The performance of the control system is evaluated through simulations under different operating scenarios to verify the proposed method.