Development of a practical control-oriented mathematical model for gas pressurizer

As the nuclear reactor's intelligence, the Pressurizer (PRZ) controls pressure and water volume (or level) during operating fluctuations. Due to the unique characteristics of Gas-PRZ (GPRZ), this system is expected to be an alternative of choice for the progress of Small Modular Reactors (SMRs). This paper derives the Non-Linear Model (NLM) for GPRZ based on mass and energy conservation equations. Then, the NLM is linearized in order to present the transfer function model as a Control-Oriented Mathematical Model (COMM) under in-surge and out-surge scenarios. Also, the GPRZ of the WHPCHF (Wisconsin High-Pressure Critical Heat Flux) facility has been used for assessing the COMM. In the current research, the qualification results demonstrate that the COMM is compliant with the Aspen HYSYS outputs. In addition, a PID controller is designed for GPRZ to demonstrate the practical use of COMM. In fact, the results reveal that the COMM can act as a useful model for GPRZ in ongoing research.