Multimodular load following coordinated control of high temperature gas-cooled reactor nuclear cogeneration plants

Due to their enhanced safety and flexibility, small modular reactors (SMRs) show great promise in nuclear energy applications. The modular high-temperature gas-cooled reactor (mHTGR) is a typical SMR with the advanced design features of high temperature and inherent safety. By adopting the multimodulear scheme, where multiple mHTGR-based reactor modules are used to drive common thermal load equipment, any desired power ratings can be reached. The multimodular mHTGR plants are suitable for supplying clean power and heat to the microgrids or industrial complexes, where the load following capability is crucial in flexible operation. As its reactor modules are coupled together by the common load equipment, the key issue in realizing the load following control of a multimodular nuclear plant is to stabilizing the main steam pressure by the modules themselves in a coordinated manner. However, the current results in the coordinated control of multimodular nuclear plants require that the main steam pressure should be stabilized by the load side, meaning that the plants are proper to operate in the base-load mode. In the context of improving flexibility, a multimodular load-following coordinated control method is proposed in this paper, which converts the load following coordination to the flowrate-pressure joint control of common secondary fluid flow network (FFN). It is proved that the globally bounded closed-loop stability can be provide by a simple distributed adaptive control needing only local measurements. Simulation results show the feasibility and satisfactory performance of the proposed multimodular load following control method.