Robust Output Feedback Adaptive Control of Nuclear Reactor

This paper presents an output feedback Robust Model Reference Adaptive Control (RMRAC) for control of a Pressurized Water Reactor (PWR). The main advantage of the proposed method is that it does not need explicit model parameter information. The nonlinear model for reactor core dynamics is considered based on normalized point kinetics equations, with one equivalent delayed neutron group and temperature feedback from lumped fuel and coolant temperatures. The nonlinear equations are linearized and recast as a transfer function model to perform control studies. The ideal controller gains are computed by assuming that the numerator and denominator coefficients are known at nominal power. Thereafter, adaptive laws are designed to handle parametric uncertainties and external disturbances over the operating power levels. The impact of external disturbances in output power is minimized with the help of over parametrized controller structure. Additionally, $\sigma$ modification is considered to make the adaptive laws robust. The stability of signals is verified through Lyapunov analysis and Barbalat's Lemma. The efficacy of the proposed controller is compared with the standard MRAC and the state feedback assisted controller (SFAC) through simulations.