MODEL-FREE ADAPTIVE CONTROL FOR MHTGR-BASED NUCLEAR STEAM SUPPLY SYSTEMS

摘要

Modular high temperature gas-cooled reactor (MHTGR) uses helium as coolant and graphite as both moderator and structural materials. Due to its inherent safety feature, MHTGR has been regarded as an important candidate for next generation of nuclear plants. By coupling with the once-through steam generator (OTSG), MHTGR can be utilized to form the nuclear steam supply system (NSSS) for producing superheated steam, which can be adopted for nuclear plants with high efficiency. Power-level control of is important for the stable and efficient operation of the MHTGR-based NSSS, and it is necessary to develop the power-level control law that is robust to physical and thermal parameters and can guarantee the closed-loop stability in normal and even abnormal conditions. In this paper, a model-free adaptive power-level control law is developed for the MHTGR-based NSSS, which is free from physical and thermal-hydraulic parameters, takes the simple forms of proportional-integral (PI) or proportional-differential (PD) feedback law, and can provide globally asymptotic closed-loop stability. Then, it is applied to the NSSS control of the two modular high temperature gas-cooled nuclear plant HTR-PM. Numerical simulation results in normal power maneuver and some typical abnormal cases show that this new control law can provide satisfactory closed-loop stability as well as transient performance.