Research on Dynamic Characteristics of PWR Nuclear Power Unit under Variable Power Loads Based on APROS
-
摘要: 利用仿真软件APROS,基于模块化建模方法,搭建了包含一、二回路主要设备的百万千瓦级压水堆核电机组动态仿真模型,并进行了稳态工况与动态过程的仿真验证。在此基础上,研究了不同速率的线性降负荷与不同幅度的阶跃降负荷下核电机组主要参数的动态变化。结果表明:阶跃降负荷幅度小于等于2%满功率(FP)时,一回路平均温度波动小,不能引起控制棒的动作;当阶跃降负荷幅度大于2%FP且小于等于5%FP时,回路平均温度波动引起控制棒动作但很快回到温度死区,最终稳定的回路平均温度反而高于初始温度;负荷线性变化过程中稳压器压力波动最大可达到0.3 MPa;由于冷却剂比容与温度呈正相关,稳压器相对水位变化与回路平均温度变化趋势基本一致。本研究旨在为压水堆核电厂灵活运行提供理论参考。Abstract: A dynamic model of the million kilowatt PWR unit including the main equipment of the primary and secondary circuits was built based on the modular modeling method by using the simulation software APROS. The steady-state and dynamic processes were simulated and verified. The dynamic characteristics of the main parameters of the system under the different rates of linear load shedding and different step load shedding were studied. The results show that when the step load reduction is less than or equal to 2% full power (FP), the average temperature (Tavg) fluctuation in the primary circuit is small, which cannot cause the action of control bar; when the step load reduction is greater than 2%FP and less than or equal to 5%FP, the Tavg fluctuation causes the control bar to act but quickly returns to the temperature dead zone. Eventually, the stabilized Tavg ended up higher than the initial temperature. In the process of linear load change, the maximum pressure change of the pressurizer can reach 0.3 MPa. Since the specific volume of coolant is positively related to the temperature, the changing trend of the pressurizer water level is consistent with that of the average temperature of the loop. The purpose of this study is to provide theoretical reference for the flexible operation of PWR nuclear power plant.
-
Key words:
- PWR /
- Dynamic characteristics /
- System modeling /
- Reactor power control
-
表 1 某核电机组设计工况的主要热力参数
Table 1. Main Thermal Parameters of Design Conditions of Nuclear Power Unit
热力参数 参数值 堆功率/MW 3400 汽轮机功率/MW 1251 主泵热功率/MW 15 回路平均温度/℃ 300.9 主蒸汽压力/MPa 5.53 额定蒸发量/(kg·s−1) 1888.6 反应堆冷却剂系统(RCS)热工最佳估算流量/(kg·s−1) 15170 表 2 稳态参数理论值与模拟值比较
Table 2. Comparison Between Theoretical and Simulated Values of Steady-State Parameters
参数 100%FP工况 90%FP工况 设计值 模拟值 误差/% 设计值 模拟值 误差/% 堆功率/MW 3400 3422 0.65 3113 3134.26 0.68 热管段平均温度/℃ 321.1 321.24 0.04 318.06 319.3 0.39 主蒸汽压力/MPa 5.53 5.62 1.63 5.59 5.89 5.37 主蒸汽温焓/(kJ·kg−1) 2783.7 2787.9 0.15 2783.6 2785.2 0.06 再热蒸汽压力/MPa 0.932 0.937 0.54 0.839 0.858 2.26 再热蒸汽焓/(kJ·kg−1) 2961 2964 0.10 2969.4 2971 0.05 凝汽器工作压力/kPa 4.40 4.42 0.45 4.40 4.41 0.23 主给水焓/(kJ·kg−1) 975.7 976.34 0.07 949.5 953.6 0.43 -
[1] 鉴庆之,孙东磊,王超凡,等. 高比例可再生能源电网消纳及调峰灵活性评估[J]. 山东大学学报:工学版,2022, 52(5): 123-131,140. [2] 王建强,戴志敏,徐洪杰. 核能综合利用研究现状与展望[J]. 中国科学院院刊,2019, 34(4): 460-468. [3] 王瑞林,孙杰,洪慧. 可再生能源与燃煤发电集成互补系统综述[J]. 洁净煤技术,2022, 28(11): 10-18. [4] DONG Z, PAN Y F. A lumped-parameter dynamical model of a nuclear heating reactor cogeneration plant[J]. Energy, 2018, 145: 638-656. doi: 10.1016/j.energy.2017.12.153 [5] VAJPAYEE V, BECERRA V, BAUSCH N, et al. Dynamic modelling, simulation, and control design of a pressurized water-type nuclear power plant[J]. Nuclear Engineering and Design, 2020, 370: 110901. doi: 10.1016/j.nucengdes.2020.110901 [6] 吕崇德, 任挺进, 姜学智, 等. 大型火电机组系统仿真与建模[M]. 北京: 清华大学出版社, 2002: 19-28. [7] 杨江,田文喜,苏光辉,等. AP1000冷管段小破口失水事故分析[J]. 原子能科学技术,2011, 45(5): 541-547. [8] 李想,孙皖,丁书华,等. 基于RELAP5的LOCA喷放阶段下降段内CCFL特性研究[J]. 核动力工程,2022, 43(3): 58-65. [9] WAHID A, SUNDARI T, RATIKO R. Dynamic modeling and controlling of a spent nuclear fuel storage pool under periodic operation and station blackout conditions[J]. Annals of Nuclear Energy, 2022, 166: 108751. doi: 10.1016/j.anucene.2021.108751 [10] 赵利刚. 基于APROS的核电站加热器建模与仿真[J]. 能源与节能,2016(4): 90-91,178. [11] 田培妤,李毅,梁铁波,等. 基于APROS的核动力系统建模与仿真研究[J]. 核动力工程,2022, 43(4): 154-161. [12] 吴国旸,鞠平,宋新立,等. 电力系统动态仿真中AP1000核电机组的简化实用模型[J]. 中国电机工程学报,2017, 37(6): 1657-1665.