METHOD OF OPERATING A NUCLEAR REACTOR WHICH MAINTAINS A SUBSTANTIALLY UNIFORM AND SYMMETRIC AXIAL POWER DISTRIBUTION PROFILE WITH CHANGES IN LOAD

摘要

1493735 Controlling nuclear reactors WESTINGHOUSE ELECTRIC CORP 20 Aug 1975 [29 Aug 1974] 34536/75 Heading G6C The reactivity of a nuclear reactor, e.g. a pressurized water reactor, having an axially extending core, is controlled by the axial insertion and removal of full length control rods and also by varying the concentration of a neutron absorbing material in a core coolant, in such a way that a substantially uniform and symmetrical axial power distribution is maintained during normal reactor operation. In one embodiment, the neutron absorbing material, e.g. boron, is used to control reactivity changes associated with changes in power, and the full length control rods are mainly used to adjust variations in axial power distribution. In another embodiment, the full length control rods are associated with changes in power, part length control rods are used to adjust the axial power distribution, and the neutron absorbing material is used to compensate for xenon build-up or depletion.