Study on power control methodology of the Accelerator Driven sub-critical reactor system

Abstract

The Accelerator Driven sub-critical reactor System (ADS) is an innovative system for the utilization of nuclear energy, for which the strategy of power control is different from the current critical reactor. In this paper, the physical model of the sub-critical reactor core of ADS was built according to the point space-time neutron kinetics equations with delayed neutrons produced by precursor nuclides of one equivalent group. The linear approximation of equations was done near the steady working point, based on which, the kinetic neutronics and thermal characteristics of ADS were analyzed, and the strategy of power control system of the sub-critical reactor core of ADS was studied. A constant power control system was designed by means of the Proportion-Integral Derivative (PID) controller and the Linear Active Disturbance Rejection Controller (LADRC). The controllers were tuned in the linearized model and then tested in the actual nonlinear model by means of Matlab/Simulink. The results show, that for both methods, the control system can avoid the disturbances induced by the external neutron source intensity or the reactivity, and make the power constant with little over shoot and short settling time, and the control effect of LADRC is better than PID.