Experimental evaluation of digital control schemes for nuclear reactors

Experiments have been conducted on the 5 MWt fission reactor, MITR-II, in which fault-tolerant control schemes were tested and evaluated under both transient and steady-state conditions. These control systems incorporated on-line detection, isolation and reconfiguration of faulty equipment, sensor calibration, measurement estimation, and information display in given controller structures [1, 2]. Among the techniques studied were ones simulating operator instructions, heuristic programing including both adaptive and learning theory routines, and predictive methods. Each method studied resulted in digital control of reactor power via analysis of a validated estimate of plant conditions (power, temperature, flow) obtained from the plant´s sensors. The control schemes also used estimates of reactivity obtained via either balances or an analytic measurement employing inverse kinetics [1, 3].