Sliding mode control design for a PWR nuclear reactor using sliding mode observer during load following operation

Reactor power control is one of the most important problems in a nuclear power plant. In this paper, a sliding mode control system which is a robust nonlinear controller is designed to control the Pressurized-Water Nuclear Reactor (PWR) Power. The reactor core is simulated based on the point kinetics equations and three delayed neutron groups. Considering neutron absorber poisons and regarding the limitations of the xenon concentration and delayed neutron precursors densities measurement, a sliding mode observer is designed to estimate their values and finally a sliding mode control based on the sliding mode observer is presented to control the reactor core power. The stability analysis is given by means Lyapunov approach, thus the control system is guaranteed to be stable within a large range. The employed method is easy to implement in practical applications and moreover, the sliding mode control exhibits the desired dynamic properties during the entire output-tracking process independent of perturbations. Simulation results are presented to demonstrate the effectiveness of the proposed controller in terms of performance, robustness and stability.