Synthesis of Digital Control Systems for Nuclear Reactors, (I)

Abstract

The present work is an attempt to synthesize an optimal closed-loop control system for controlling the transition from one power level to another in nuclear reactors. This first report covers a study on optimal solutions, undertaken with a view to gaining a better understanding of the basic characteristics possessed by such solutions, and to providing useful guides to the synthesis of closed loop control systems. The reactor system model adopted here is a three-dimensional nonlinear discrete-time system of about twenty sampling intervals, which makes it impracticable to apply the conventional dynamic programming method, on account of the excessive demands on computer time and core memories. To overcome this difficulty, a method termed “regionwise dynamic programming” is adopted, to handle the nonlinear multi-stage discrete time system. Some discussions are presented concerning the accuracies obtained and the range of applicability of the present method. The numerical solutions solved by this proposed method can be considered almost exact and physically reasonable. These solutions shall be utilized in a forthcoming paper for synthesizing control systems.