为保障主机同轴给水泵机组的运行安全，以某660MW配置主机同轴给水泵的超超临界机组为例，基于GSE动态仿真软件，建立了其热力系统动态模型，采用仿真模拟与理论分析相结合的方法，计算了主机给水泵发生故障后，配置应急电泵容量及旁路安全阀开启策略对机组运行安全的影响规律。结果表明：主机同轴给水泵发生故障后，开启应急电泵，主蒸汽压力迅速下降，大约300s左右，主汽压力达到稳定值；应急电泵容量对应负荷为30%~50%THA，应急电泵的容量越大，压力达到稳定所需时间越短；主再热汽温变化趋势与应急电泵容量直接相关，当容量增加至40%THA负荷对应给水流量值时，主再热汽温先下降后上升，最终到达与容量值配置值的新稳态工况；过早开启旁路安全阀泄压易诱发省煤器汽化，威胁机组运行安全；应急电泵容量对应负荷为30%~50%THA时，安全阀开启时间由360s下降到220s；当应急电泵容量太低时，无法将锅炉系统内过多的热量及时带走，最小容量配置为35%THA工况对应的给水流量值。

To ensure the safe operation of the main engine coaxial feedwater pump unit, a dynamic model of the thermal system of a 660MW ultra-supercritical unit equipped with a main engine coaxial feedwater pump was established in this paper. The influence of the emergency electric pump capacity and the bypass safety valve opening strategy on the unit operation safety after the main engine feedwater pump failed was calculated. The research shows that after the main engine coaxial feedwater pump fails, the emergency electric pump is turned on, the main steam pressure drops rapidly, and the main steam pressure reaches a stable value in about 300s; the capacity of the emergency electric pump corresponds to a load of 30%~50%THA. The larger the capacity of the emergency electric pump, the shorter the time required for the pressure to reach stability; the trend of the main reheat steam temperature change is directly related to the capacity of the emergency electric pump. When the capacity increases to the feedwater flow value corresponding to the load of 40%THA, the main reheat steam temperature first decreases and then increases, and finally reaches a new steady-state condition corresponding to the capacity value configuration value; premature opening of the bypass safety valve to release pressure is likely to induce economizer vaporization, threatening the safe operation of the unit; when the capacity of the emergency electric pump corresponds to a load of 30%~50%THA, the opening time of the safety valve decreases from 360s to 220s; when the capacity of the emergency electric pump is too low, it cannot take away the excessive heat in the boiler system in time, and the minimum capacity is configured to the feedwater flow value corresponding to the 35%THA condition.

TM 621

内蒙古电力集团(有限)责任公司内蒙古电力科学研究院分公司项目资助(发文号：电科院(2022)94号)；中国博士后科学基金(2024T170703)。