摘要
发电厂闭式循环水系统一般采用扩大单元制运行方式,当并列机组循环水泵出力不同时,会产生窜流现象,导致进入凝汽器的循环水流量与循环水泵母管出口流量不相等,从而影响循环水系统优化调度计算的准确性,目前尚未有窜流量准确测算方法。为此,以某发电厂为例分析了闭式循环水系统构成原理,确定基于流量平衡的窜流量计算方法,并结合循环水泵流量扬程曲线数据,得到窜流量与并列机组距出口母管最近循环水泵扬程差的数学计算模型,实现循环水系统所有管道流量数据的在线计算。最后,通过与热平衡法和超声波流量计测量的凝汽器循环水流量对比分析,建议循环水扩大单元制运行机组优先考虑采用基于窜流量计算法测量凝汽器循环水流量。
The closed circulating water system of a power plant generally adopts the operation mode of an expanded unit system.When the output of circulating water pumps of parallel units is different,there will be channeling flow.Under such circumstances,the circulating water flow entering the condenser is not equal to the outlet flow of the circulating water pump header,which affects the accuracy of the optimal dispatching calculation of the circulating water system.At present,there is no accurate calculation method for channeling flow.Therefore,a power plant is taken as an example to analyze the composition principle of the closed circulating water system and determine the calculation method of channeling flow based on flow balance.Based on the flow head curve data of the circulating water pump,the mathematical calculation model of channeling flow and the head difference of the circulating water pump closest to the main outlet pipe of parallel units is obtained to realize the online calculation of flow data of all pipelines of circulating water system.Finally,the condenser circulating water flow measured by the heat balance method and the ultrasonic flowmeter is comparatively analyzed.It is recommended to adopt the channeling flowbased calculation method to measure the condenser circulating water flow of units under the operating mode of the expanded unit system.
作者
邵建宇
孙永平
奚宇
SHAO Jianyu;SUN Yongping;XI Yu(Zhejiang Zheneng Taizhou Second Electric Power Generation Co.,Ltd.,Taizhou,Zhejiang 317108,China;Zhejiang Energy R&D Co.,Ltd.,Hangzhou 310014,China)
出处
《浙江电力》
2023年第1期103-109,共7页
Zhejiang Electric Power
关键词
扩大单元制
循环水
窜流量
冷端优化
expanded unit system
circulating water
channeling flow
cold-end optimization
