For all power plants, the power supply and demand must be balanced by either generation or load [4],which means that load following ability of a nuclear power plant is needed. Based on the sliding mode drawback in chattering, recursive SMC method was introduced to the reactor control design and a fuzzy-adapted nonlinear power-level control was designed for advanced boiling water reactors [6]. Model predictive control (MPC) method is an effective way to deal with the system nonlinearity.Na et al. introduced theMPC to this field [7] and applied it to design power-level control for pressurized water reactors(PWRs) [8]. For dealing with dynamical nonlinearity better, nonlinear MPC method was applied to power-level control design for PWRs [9,10]. Based on the technique of iterative damping assignment (IDA),Dong gave a nonlinear feedback power-level control to the MHTGR[11]. Although this IDA-based control can provide globally asymptotic
closed-loop stability, its expression is too complex to be implemented practically. Based on the physically-based control design approach whose key idea is to stabilize a physical system by retaining its natural dynamics beneficial to stabilization, Dong proposed a nonlinear dynamic
output feedback power-level control for the MHTGR [12]. Then,motivated by the need for dealing with the parameter uncertainty,Dong gave a nonlinear adaptive power-level control for MHTGRs [13].However, since this control has a dynamic output-feedback structure,it is still complex to be implemented. Therefore, it is necessary to design power-level control for the MHTGR with simple form and strong adaptation ability.