Adaptive Predictive Control of a Boiling Water Reactor

An adaptive predictive control system (APCS) is applied to the design of the recirculation and feedwater control systems of a boiling water reactor. The APCS uses the dead zone method to modify the adaptive law; thus, it is stable in the presence of unmodeled dynamics and bounded disturbances. Two single-input/single-output control systems are used instead of a multi-input/multi-output control system in order to simplify parameter adaptation. The interactions among the subsystems are treated as unmeasured disturbances. A simulation using the reactor model shows that the dome pressure versus recirculation pump speed subsystem is a nonminimum-phase system. To handle this system, the weighting polynomials for the system input and output are incorporated to form an augmented minimum-phase system and then the augmented system is controlled. The proposed algorithm is stable, does not require persistent excitation of the reference input, and performs well, which makes it practical for implementation.