Nonlinear Coordinated Control for MHTGR-Based Nuclear Steam Supply Systems

Because of its inherent safety feature and potential economic competitiveness, modular high temperature gas-cooled reactor (MHTGR) has been seen as one of the best candidates for building the next generation nuclear plants. As a typical small modular reactor (SMR), MHTGR can be incorporated with new energy resources to build micro-grids, and can also be utilized to build large nuclear energy systems having inherent safety feature at any power rating. The nuclear steam supplying system (NSSS) of MHTGR-based plants is composed of an MHTGR and a once-through steam generator (OTSG). The NSSS coordinated control is crucial for providing the load-following function. Motivated by this, a nonlinear coordinated control for MHTGR-based NSSSs is proposed in this paper. Based upon theoretical analysis, sufficient conditions for this newly-built control law to guarantee globally asymptotic closed-loop stability are given. The feasibility of this novel coordinated control strategy is verified through numerical simulation, and simulation results show that this new control law can provide satisfactory regulating performance for the NSSS by properly choosing its feedback gains. Moreover, this coordinated control has a very simple form, which means that it can be easily implemented in practical engineering.