Investigation of a suboptimal controller design for a nuclear reactor system.

Abstract

The optimal control problem of a typical nuclear reactor power plant, which is described by a ninth-order nonlinear differential equation, having time-varying parameters, is considered. The nonlinear model complicates the optimal controller synthesis. Therefore, the approach of this work is to approximate the response of the reactor system by that of a second-order linear model. The model parameters are chosen to minimize the derivations between the system and model responses using a search routine. The optimal feedback parameters computed for the second-order model 5s used for suboptimal control of the system. The model parameters are updated to reflect the system nonlinearities as well as changes in the system parameters; the corresponding control scheme is adaptive. It is shown that for the operating conditions considered, the adaptive controller need not be on-line. Also, investigation of the effects of different weighting factors in the cost function, and the effect of various control rod configurations on the system response are presented.