首页|Active Disturbance Rejection Control based on the Non-linear Extended State Observer via Sliding Mode Controller for Pressurized Water nuclear Reactors in Load-Following Operation with bounded axial power oscillations
Active Disturbance Rejection Control based on the Non-linear Extended State Observer via Sliding Mode Controller for Pressurized Water nuclear Reactors in Load-Following Operation with bounded axial power oscillations
Ansarifar, Dr. Hamid Reza Ansarifar, Dr. Gholamreza
Active Disturbance Rejection Control based on the Non-linear Extended State Observer via Sliding Mode Controller for Pressurized Water nuclear Reactors in Load-Following Operation with bounded axial power oscillations
Active Disturbance Rejection Control based on the Non-linear Extended State Observer via Sliding Mode Controller for Pressurized Water nuclear Reactors in Load-Following Operation with bounded axial power oscillations
摘要
Load-following operation in Pressurized Water Reactors (PWRs) poses significant challenges due to the nonlinear, time-varying dynamics of the reactor core, the presence of Xenon-induced spatial power oscillations, and various external disturbances. To address these challenges, this paper for the first time, proposes a novel control strategy via Active Disturbance Rejection Control (ADRC) combining a Nonlinear Extended State Observer (NESO) and a Sliding Mode Controller (SMC) for a PWR. A two-point core kinetics model with three groups of delayed neutron precursors is employed, incorporating both temperature and Xenon reactivity feedbacks to realistically represent the axial power distribution. The NESO is designed to estimate immeasurable state variables and the total disturbances term, which is then actively rejected by the ADRC framework, while the SMC ensures accurate tracking of the desired relative power. The stability of the closedloop system is rigorously analyzed using Lyapunov theory. The performance of the proposed ADRC-SMC-NESO scheme is evaluated against a linear counterpart (ADRC-SMC-LHESO) under three realistic scenarios involving gradual, moderate, and rapid power changes, as well as temperature and reactivity disturbances, over a 50-hour simulation period at the beginning of core life (BOC). Simulation results demonstrate that the proposed controller achieves lower overshoot, shorter settling time, smoother control signals, and reduced chattering compared to the linear observer-based scheme. Furthermore, the NESO provides significantly more accurate and faster state estimation. The Axial Offset (AO) and Axial Xenon Oscillation Index (AXOI) are maintained within safe bounds throughout all scenarios, confirming the effectiveness of the proposed method for safe load-following operations in PWRs.