Modeling and Control Scheme Design of a Multi-Modular High Temperature Gas Cooled Reactor Cogeneration Unit

Abstract The Multi-Modular High Temperature Gas-cooled Reactor (MHTGR) is equipped with inherent safety features and boasts numerous advantages, notably its capacity to generate high outlet steam temperatures. By leveraging the potential of the high-temperature gas-cooled reactor for cogeneration, it is possible to fully exploit its strengths and enhance its economic feasibility. Compared to MHTGR power generation unit, the multi-modular high-temperature gas-cooled reactor combined heat and power (CHP) system is more intricate, primarily due to the interconnection between heat load and electrical load. Its operating conditions are more diverse, encompassing the necessity to adapt to heat load fluctuations and to track heat load. Therefore, investigating the dynamic characteristics of the multi-modular high-temperature gas-cooled reactor CHP unit is of great significance for the subsequent design of relevant coordinated control schemes. The focus of the present study is a superheated steam generation system utilizing steam conversion technology. This system extracts heat from the high-temperature reactor main steam to raise the temperature of desalinated water, producing high temperature, high-pressure steam for supply to a chemical industrial park. In this study, dynamic models were developed for each component and integrated for simulation purposes. The open-loop dynamics of the model complied with the analysis, and the model exhibited good simulation accuracy, with most of the process parameters deviating by less than 15% from the set values. A control scheme for superheated steam temperature and pressure has been designed. The closed-loop responses of the system under two operating conditions confirmed the correctness and effectiveness of the designed control scheme.