Robust Observer-based Sliding Mode Control of a Pressurized Water Reactor

Approximations and uncertainties in system modeling lead to inaccurate state estimation and thereby the failure of systematically designed control techniques. A robust control technique is therefore needed for state estimation and control when the system is complex and is accompanied by uncertainties. One of the robust control techniques is sliding mode control (SMC). Sliding mode control is a non-linear control technique with remarkable properties like robustness and insensitive to disturbances. Hence, it is highly recommended for the control of extremely complex plants, like nuclear reactors. However, chattering is one of the main disadvantages that arise while using a sliding mode control. In this paper, a sliding mode technique is used for estimating neutron precursor density, xenon, and iodine concentrations which otherwise are very difficult to measure, and then a sliding mode controller with a reduced chattering effect is proposed for pressurized water reactor (PWR). Stability analysis of the system is carried out using the Lyapunov approach. Simulation results are presented to show the efficiency of the proposed system.