某660MW超临界机组空冷系统运行优化研究  

Numerical Investigation of Operation Optimization of 660MW Supercritical Air Cooling System

作　　者：薛康康 XUE Kang-kang(China Datang Corporation Science&Technology Research Institute Co.,Ltd.,Northwest Branch,Xi'an 710065,China)

机构地区：[1]中国大唐集团科学技术研究院有限公司西北电力试验研究院,西安710065

出　　处：《汽轮机技术》2021年第4期311-314,共4页Turbine Technology

基　　金：河北省自然科学基金项目(E2020502001)。

摘　　要：为了对某660MW超临界空冷机组空冷系统进行优化,建立了该机组空冷凝汽器变工况计算模型,并对影响排汽压力的主要因素进行分析。研究结果表明:随着风机运行台数的增加、风机运行频率的升高,机组排汽压力均降低;随着风机运行台数或频率的逐渐降低,排汽压力升高愈发剧烈,此时要注意安全运行;最佳频率所对应的排汽压力随着负荷增加而升高,低负荷低环境温度时,排汽压力维持在阻塞背压附近,高负荷高环境温度时,排汽压力增加逐渐加剧。最终提出优先降低空冷风机运行频率,当空冷风机运行频率低于规定最低频率时,再减少空冷风机运行台数的策略,得到该机组运行最佳排汽压力所对应的最佳空冷风机运行频率曲线,为同类型机组空冷风机优化运行提供参考。As to optimize the 660MW supercritical air-cooled system,the variable condition models of the air-cooled condenser were established and the main factors which affected the exhaust steam pressure were analyzed.The results show that the exhaust pressure decreases with the increase of the number of fans and the increase of the fan running frequency.With the gradual decrease of the number or frequency of the fan,the increase of exhaust pressure becomes more and more severe.At this time,attention should be paid to safe operation.The exhaust pressure corresponding to the optimal frequency increases with the increase of load.At low load and low ambient temperature,the exhaust pressure is maintained near the blocking back pressure;at high load and high ambient temperature,the exhaust pressure increases gradually.Finally,the paper puts forward the strategy of reducing the operation frequency of air-cooled fan in priority.When the operation frequency of air-cooled fan is lower than the specified minimum frequency,the strategy of reducing the number of air-cooled fans is proposed.The optimal operation frequency curve corresponding to the optimal exhaust pressure of the unit is obtained,which provides reference for the optimal operation of air-cooled fan of the same type of unit.

关 键 词：直接空冷 运行优化 最佳真空 最佳风机频率 

分 类 号：TK221[动力工程及工程热物理—动力机械及工程]