摘要
处于环境风作用下的直接空冷机组,受轴流风机群的群抽效应和热风回流的耦合作用,致使不同区域风机的冷却能力发生复杂变化。针对夏季主导风向下运行的某2 330 MW直接空冷机组,将其空冷风机群分9个区,开展热力性能实验。利用实验数据,有针对性地考虑环境气象条件、不同分区风机群转速等运行参数对机组背压的综合作用,建立最小二乘支持向量机背压预测模型,分析了空冷岛风机群转速分区调节对机组背压的影响规律:适当降低受热风回流影响较大区域的风机转速,反而可以起到降低机组背压的作用;不同分区的风机转速发生变化,对机组背压的影响明显不同;改变一台机组空冷风机的转速,也会对另一台机组的背压产生影响。实验验证表明,所建立的最小二乘支持向量机背压预测模型可以有效的抑制输入参数噪声产生的相对误差,分析结果具有可靠性。
For a direct air-cooled power generating unit exposed to the environmental wind, fan cooling capacity in different areas of the air-cooled condenser （ACC） will be observed complex variation influenced by the coupling effects of axial fan cluster pumping and exhaust recirculation. Taking two 330 MW direct air-cooled generating units running in the summer-dominant wind as an object, thermal performance tests were carried out on the nine divided portions out of the axial flow fan cluster. Based on the experimental data, the least squares support vector machine （LS-SVM） model for unit back pressure prediction was established, with due consideration being given to the combined effects of environmental and meteorological conditions and operating parameters, such as fan speeds at different portions of fan cluster, on back pressure. The influence of divisional regulation of the air-cooled fan cluster rotation speed on back pressure variation was analyzed. The results indicate that reducing appropriately fan rotation speed at the portions heavily affected by hot exhaust recirculation can reduce the back pressure. The influence of fan speed changes on back pressure differs greatly with the portions. If the air cooling fan speed of one power generating unit is changed, the back pressure of the other unit will also be impacted. The experimental verification shows that the present LS-SVM back pressure prediction model can effectively suppress the relative errors of the noise generated by the input parameters, and the analysis results have high reliability.
出处
《中国电机工程学报》
EI
CSCD
北大核心
2013年第17期71-77,14,共7页
Proceedings of the CSEE
基金
国家重点基础研究发展计划项目(973项目)(2008CB219804)
中央高校基本科研业务专项资金项目(12TD03)~~
关键词
直接空冷凝汽器
轴流风机群
背压
分区调节
air-cooled condenser
axial flow fan cluster
back pressure
divisional regulation
