Study on Dynamics of Steam Dump System in Scram Condition of Nuclear Power Plant

摘要

During the scram or load rejection of nuclear power plant, the excess steam of steam generator needs to be dumped to the main condenser through the steam conditioning device to reduce the temperature rising of the primary loop and prevent the steam generator from over-pressure. For study of the dynamics and control strategy of the steam dump system, this paper established a simulation model of nuclear power plant using Gsuite simulation platform, and then studied the dynamical-varying of some important-variables in nuclear power plants during scram. The results indicated that the model built can approximately predict the dynamic changes of important parameters such as the average temperature of the primary loop and the main steam pressure. Therefrom it is concluded that the joint operation of the steam dump system and atmospheric steam dump system can effectively prevent the rising of the temperature of the primary loop and the overpressure of the secondary circuit, and thus it can avoid the opening of the main-steam safety valve.