[关键词]
[摘要]
再热蒸汽系统的稳定性影响着燃煤机组的安全性和经济性。本文基于同一集团6台机组(A~F)的运行数据进行再热蒸汽系统的稳定性对标评价。通过3σ准则对大数据进行清洗,并利用滑动窗格法进行稳定工况划分。基于过程能力指数Cpk和变异系数CV分别对再热蒸汽温度和再热器减温水调节阀开度进行稳定性打分,并利用层次分析法-优劣解距离法对参数进行权重分配计算,完成不同机组在不同工况下的综合对标评价。结果表明:A~F机组中,E机组再热汽温对应的Cpk值最大,为1.75,其稳定性最好;F机组再热器减温水调节阀开度对应的CV值最小,为0.56,其稳定性最好;A机组的再热蒸汽温度和再热器减温水调节阀开度的稳定性最差;A机组和C机组左右汽温偏差和再热器减温水调节阀开度差明显偏大,源于其采用四角切圆方式燃烧;300 MW的E机组再热蒸汽系统的稳定性最好,百万机组再热蒸汽系统的稳定性较差。
[Key word]
[Abstract]
The stability of reheat steam system of coalfired unit affects the safety and economy of the system. Based on the operation data of 6 units (A to F) of the same group corporation,the stability benchmarking evaluation of reheat steam system was carried out in this paper. The big data was cleaned through the 3σ criteria,and the stable working conditions were classified by using the sliding pane method. Based on the process capability index Cpk and coefficient of variance CV,the stability of reheat steam temperature and desuperheating water regulating valve opening of reheater was scored respectively,and the weight distribution of parameters was calculated by analytic hierarchy processtechnique for order preference by similarity to ideal solution (AHPTOPSIS) to complete the comprehensive benchmarking evaluation of different units under different working conditions. The results show that in units A to F,the corresponding value of reheat steam temperature of unit E is the largest,Cpk is 1.75,and its stability is the best; the corresponding value of desuperheating water regulating valve opening of reheater of unit F is the smallest,CV is 0.56,and its stability is the best;the stability of reheat steam temperature and desuperheating water regulating valve opening of reheater of unit A is the worst.The left and right steam temperature deviation of unit A and unit C and the difference of desuperheating water regulating valve opening of reheater are obviously too large,which is due to its fourcorner tangential combustion;the reheat steam system of 300 MW unit E has the best stability,and the reheat steam system of 1 000 MW unit has poor stability.
[中图分类号]
TK221
[基金项目]
国家重点研发计划项目(2018YFB060420103)