Session: 04-06: SMRs, Advanced Reactors and Fusion

Paper Number: 131854

131854 - Dynamic Modeling of Modular High Temperature Gas-Cooled Reactor Cogeneration System and Control Design Under the Condition of Turbine Isolation 

Abstract: 

The HTR-PM600 modular high temperature gas-cooled reactor (mHTGR) has the advantages of inherent safety and high steam quality, and its application to combined heat and power supply can improve its economy. Shandong Shidao Bay Demonstration Project HTR-PM with two modules has been connected to the grid for power generation in 2022. At present, the cogeneration plant project is under construction, with 6 mHTGR modules operate in parallel. However, the use of once-through steam generator (OTSG) and the characteristics of multi-module make nuclear steam supply system (NSSS) difficult to control. Because OTSG has small thermal inertia, easy to dry out. Multiple modules supply gas to the heat load through the same main steam pipe, resulting in mutual coupling between modules. When the turbine is isolated, the operation and control characteristics of the system are very different from normal operating conditions, as evidenced by the inability of the turbine's main steam regulator valve to participate in the pressure control of the steam generator. It is necessary to increase the level of automation to ensure the safe and stable operation of the nuclear cogeneration plant. System dynamic modeling is the basis of control design and verification. The object-oriented physical modeling Simscape toolbox based on MATLAB/Simulink platform can form a simulation object model by connecting independent physical components, which makes modeling easier. And Simscape has good compatibility with Simulink, which make it convenient to imply control design using Simulink. A mHTGR cogeneration power plant is modeled based on MATLAB/Simulink, including NSSS, conventional island which containing the industrial steam supply system. The steady state simulation tests at typical operation condition points and the dynamic response experiments were carried out to verify the rationality and accuracy of the model, which has the feasibility to be used for control system design and verification. Based on the established model, the control scheme for NSSS under the turbine isolation condition is designed, , which regulates the feedwater pumps and valves at the steam generators’ inlet.  Simulation results show that the control scheme and control law can ensure the safe and stable operation of the cogeneration plant, it also can realize the load following of cogeneration plant without turbine, and the response is fast and accurate enough under serval typical transient conditions. Due to the good compatibility and scalability of MATLAB/Simulink platform, this model is also planned to be used in the control design of other operation condition and intelligent control algorithm with the help of python in the future.

Presenting Author: Xuan Lin Institute of Nuclear and New Energy technology, Tsinghua University

Presenting Author Biography: Master student of Tsinghua University, engineer trainee of China Institute of Atomic Energy.

Authors:

Xuan Lin Institute of Nuclear and New Energy technology, Tsinghua University
Zhe Dong Institute of Nuclear and New Energy technology, Tsinghua University
Fan Chen Institute of Nuclear and New Energy technology, Tsinghua University
Shuqiao Zhou Institute of Nuclear and New Energy technology, Tsinghua University
Chao Guo Institute of Nuclear and New Energy technology, Tsinghua University
Duo Li Institute of Nuclear and New Energy technology, Tsinghua University
Weidong Sun Institute of Nuclear and New Energy technology, Tsinghua University