Step dynamic process of the hydraulically-driven control rod, (II) Theoretical model ore step-down process

The HCRDS (hydraulic control rod driving system) is a new type of control r od driving system, which is designed by INET (Institute of Nuclear Energy T echnology) and has been put into use in 5 MW nuclear heating reactor in Tsi nghua University. The purpose of this paper is to theoretically analyze the step-down process of this new technology and establish fundamental basis f or further analysis and research. The experimental loop of the HCRDS and the working principle on the step-do wn process are introduced in this paper. The theoretical model is establish ed on the basis of analysis, simplification and hypothesis. Also given is t he accurate mathematical description of this model. The comparison between the results of this model and that of the experiment proves the rationality and feasibility of the model. The selection of the working point is also i ntroduced.