Load-follow operation with the MSHIM control system

As part of Westinghouse Electric Corporation's ongoing efforts to improve plant daily load-follow capability, a system has been developed that promises a significant enhancement of current load-maneuvering capabilities, while simultaneously reducing the burden on operators and plant systems. This concept, the mechanical shim (MSHIM), control system utilizes two independently operable groups of control banks for essentially simultaneous control of reactivity and axial power distribution. This system has been developed with the goal of supporting either of two operational modes. One mode is designed to maximize spinning reserve (MAXSR) capacity (return to full-power capability). The other mode minimizes boric (MINB) acid changes, hence effluent production, during the power maneuver. The features of the two control modes are summarized