空冷凝汽器积灰软测量系统设计及实现  

Design and Practice of Soft Sensing System for Ash Accu-mulation in Air-Cooled Condenser

作　　者：孙长富 范思远 SUN Changfu;FAN Siyuan(Shenzhen Municipal Energy Conservation and Resource Comprehensive Utilization Ex-perts Federation;Northeast Electrical University Automation Engineering College)

机构地区：[1]深圳市节能与资源综合利用专家联合会 [2]东北电力大学自动化工程学院

出　　处：《上海节能》2021年第12期1389-1396,共8页Shanghai Energy Saving

摘　　要：电力能源生产过程中,空冷凝汽器的应用对传统水冷资源损耗大问题的解决作出重大贡献。但空冷凝汽器翅片间密、冗繁复杂,表面极易积灰,致使传热热阻增加、效率降低,抬高电站汽轮机排汽压力,进一步导致电站安全性下降、发电煤耗增加。因此,建立精确的管外积灰厚度软测量方法,对减少积灰的负面影响具有重大的工程实际意义。本文对现场直接空冷系统积灰换热过程进行建模,建立积灰状态下现场空冷电站传热系数及汽轮机排汽压力的运算模型。模拟并采集空冷凝汽器现场运行状态下的实时风速、温度、流量、压降等关键系统参数,并以支持向量机学习算法建立不同风速条件下(数据样本作为输入、传热系数为输出)传热系数预测模型。以预测传热系数代入积灰厚度软测量模型得出的积灰厚度变化规律可知,随风速增加,积灰沉积呈增长趋势,且积灰速率随着积灰厚度增加而逐渐降低,厚度达0.9 mm后沉积速率急剧下降。In the process of power energy production,application of air-cooled condenser makes a great contribution to the solution of the problem of large loss of traditional water-cooling resources.However,the fins of air-cooled condenser are dense and complex and the surface is very easy to accumulate ash,resulting in increased heat transfer resistance,reduced efficiency and increased exhaust pressure of steam turbine in power station.As a result,the safety of the power station is further reduced and the coal consumption for power generation is increased.Therefore,the establishment of an accurate soft sensing method for the thickness of ash deposition outside the pipe is of great engineering practical significance to reduce the negative impact of ash deposition.In this paper,the ash accumulation heat transfer process of on-site direct air cooling system is modeled and the calculation models of heat transfer coefficient and steam turbine exhaust pressure of on-site air cooling power station under ash accumulation state are es-tablished.The key system parameters such as real-time wind speed,temperature,flow and pressure drop of air-cooled condenser under on-site operation are simulated and collected and the prediction model of heat transfer coefficient under different wind speed conditions(data samples as input and heat transfer coefficient as output)is established by using support vector machine learning algorithm.Accord-ing to the variation law of ash thickness obtained by substituting the predicted heat transfer coefficient into the ash thickness soft sensing model,the ash deposition shows an increasing trend with the increase of wind speed and the ash deposition rate gradually decreases with the increase of ash thickness.After the thickness reaches 0.9 mm,the deposition rate decreases sharply.

关 键 词：翅片管积灰 实验模拟系统 传热系数 支持向量机 软测量模型 

分 类 号：TM62[电气工程—电力系统及自动化]