Regulation of differential pressure in liquid zone control system using fuzzy logic control scheme

Nuclear reactor control is one of the areas with a huge potential for application of intelligent systems including fuzzy logic, in which, however, the development is still in its infancy, despite its success in other domains. The operation of large Pressurized Heavy Water Reactors (PHWRs) e.g., the 540 MWe PHWR with flattened radial and axial flux distributions coupled with xenon poisoning effect leads to complex operational and control problems. The Liquid Zone Control System (LZCS) is provided in large PHWRs, for continuous fine control of the reactor power level and power distribution. The LZCS is a complex hydropneumatic system, in which maintaining the differential pressure between gas outlet header and delay tank is an important function, from the point of view of reactivity control. In the existing systems in India, a conventional PI controller is employed. In this paper, fuzzy control scheme has been proposed for maintaining the pressure difference between gas outlet header and delay tank, close to a specified set point