Fuzzy adaptive backstepping load following control for MHTGRs with power error constraint and output disturbances

Abstract

This paper proposes a fuzzy adaptive backstepping controller for load following of modular high-temperature gas-cooled reactors (MHTGRs) in the presence of power error constraint and output disturbances. The mathematical model of the MHTGRs is firstly constructed based on the point-reactor kinetics equations with one equivalent delayed neutron group. After that, a fuzzy adaptive backstepping control strategy with the consideration of power error constraint and output disturbances is proposed to improve load following performance. The proposed control scheme enables the power error never to violate constraint limitation by employing the barrier Lyapunov function method. Meanwhile, the fuzzy logic system (FLS) is applied to accurately estimate model unknown lumped term which consists of unmeasured states and output disturbances, and thereby enhancing the disturbances rejection capability and robustness of the proposed control scheme. Stability analysis and the convergence of the power error are guaranteed according to the Lyapunov directly method. In the end, simulations and comparisons with conventional backstepping controller are conducted to verify the improved load following performance of the proposed fuzzy adaptive backstepping control strategy.