反应堆温度效应的稳定性影响分析

Analysis of Temperature Effect on Reactor Stability

压水型反应堆堆芯的温度效应对核电厂在瞬态工况下的反应性控制具有重要影响。对压水型反应堆温度效应产生负反应性反馈的机理进行了阐述,并基于点堆中子动力学模型,在MatLab/SimuLink的仿真环境下建立了带有温度反馈环节的瞬态工况堆芯响应仿真模型。根据所建立的仿真模型,考虑反应堆升降功率的瞬态工况,对不同的反应堆温度系数的负反馈影响进行了仿真分析。仿真分析的结果表明,当反应堆需要改变其输出功率对堆芯引入阶跃微小反应性扰动后,由于核燃料和慢化剂的负温度系数作用,使反应堆本身具备内在稳定性,堆芯中子密度变化是趋于稳定的。根据仿真结果,反应堆负温度系数所产生的温度效应对核电厂瞬态工况下反应性控制具有有利的影响。所用的堆芯仿真模型分析方法可以为反应堆堆芯功率控制系统的设计和分析提供参考。

Temperature effect will influence reactivity controlling on transient condition in pressurized water reactor core. Expound the theory of negative reactivity feedback caused by temperature effect for Pressurized Water Reactor, and established reactor core model with temperature feedback based on Point Reactor Neutron Kinetics model, to simulate the feedback caused by temperature effect. The result of simulation show that, after a small external step reactivity disturbance, reactor core neutron density is tends to be stable caused by temperature effect for negative reactivity feedback. The stability is helpful for the reactivity controlling on transient condition in nuclear power plant. The method of reactor core model simulation analysis can provide reference for reactor core power control system design and analysis.