【作者】 谢伟；

【导师】 徐二树；

【作者基本信息】 华北电力大学（北京） ， 工程热物理， 2011， 硕士

【摘要】 节能降耗是火电厂的重要任务,火电机组的年均负荷率约为70%左右,导致电厂的辅机设备长时间运行在非额定工况。由于辅机选型按最大工况配置,且裕度较大,加之运行方式不合理,使得火电机组实际运行厂用电率高于设计值,因此如何最大限度降低厂用电率已成为在役火电机组节能降耗面临的主要问题。本文分析了并联泵的运行规律,并以汽轮机侧的主要辅机凝结水泵、循环水泵为研究对象,研究其优化运行方式,为降低汽轮机侧辅机的厂用电率,优化辅机运行提供了参考依据。(1)在考虑管道阻力损失、泵出口压力限制等情况下,建立调速凝结水泵优化运行数学模型；通过实例分析,使用SQP方法求解凝结水泵优化运行数学模型,得到两台并联变频调速凝结水泵优化运行方式；通过改造前后运行方式对比,得到了变频改造的节能量；(2)分析汽轮机负荷、凝汽器真空、循环水入口温度与循环水流量之间的关系,基于最佳真空建立了循环水泵优化运行数学模型。求解循环水泵优化运行数学模型得到循环水泵在双速改造和变频改造下的优化运行方式,并指出只有长期低负荷、低循环水入口温度的机组,循环水泵变频改造比双速改造才能带来更大的经济效益。更多还原

【Abstract】 Energy saving and consumption reduction was the important task of coal-fired power plants.Thermal power unit annual average load rate of approximately 70% which leads to the auxiliary equipments were runing on non-rated conditions.Auxiliary selection condition by the largest configuration,and the large margin and unreasonable operation mode, which make the actual operation of thermal power units of auxiliary power ratio higher than the design value.How to reduce auxiliary power ratio has became a key step to successfully carry out the task.This article analysis of operation regulations of parallel pump,and condensate pump and the circulating water pump for research object in steam turbine side, do some research on optimal operation,which provides a reference for reduce the turbine side of the auxiliary power consumption rate and optimal operation auxiliary.(1)Consider the impact of the pressure loss of pipe and pump outlet pressure limits,the variable speed condensate pump of optimal operation of mathematical model was established.The SQP methods was utilized to solve mathematical model of optimal operation of condensate pumps.Optimal operation of variable speed condensate pumps in parllel and optimal operation was obtained.By comparing with the original operation,energy consumption was obtained.(2)By analyzing the relationship between turbine load, condenser vacuum, circulating water inlet temperature and the circulating water flow,optimal operation mathematical model of circulating pump was established which was Based on the theory of optimum vacuum.Solving the optimal operation mathematical model of circulating water pump, the optimal operation of renovation of circulating pump with frequency conversion renovation and two-speed transformation was acquired,and point out frequency conversion renovation could bring more economic benefits than two-speed transformation only if circulating water system was long-term operation with low load and low inlet temperature of circulating water.更多还原