Model-Free Power-Level Control of MHTGRs Against Input Saturation and Dead-Zone

The modular high temperature gas-cooled reactor (MHTGR) is an important type of small modular reactors (SMRs) with inherent safety. It is clear that power-level control is crucial in providing safe and stable operation as well as in realizing load-following function so that the MHTGRs can be grid-appropriate. However, there always exists the reactor parameter uncertainty and control input nonlinearity such as saturation and dead-zone practically, which seriously intensify the difficulty in designing power-level control. Thus, it is quite necessary to study MHTGR power-level control method against reactor parameter variation as well as control input saturation and dead-zone. Motivated by this, model-free MHTGR power-level control laws against the input saturation, dead-zone and both saturation and dead-zone are proposed in this paper, which are not only insensitive to reactor parameter but also able to compensate the control input nonlinearities. It is proved theoretically that these newly-built MHTGR power-level control laws guarantee strong closed-loop stability. Numerical simulation results illustrate the relationship between the control performance and some parameters of the controllers and input nonlinearities.