600mw超临界w型锅炉机组主汽温度低异常分析及对策.docVIP

600 MW超临界“W”型锅炉机组主蒸汽温度低的分析及处理 Abnormality analysis and countermeasure on lower main steam temperature of 600 MW supercritical W-flame boiler 黄 伟1，寻 新1，刘复平1，邹自敏2，张建玲1，彭 敏1 HUANG Wei1, XUN Xin1, LIU Fu-ping1, ZOU Zi-min2, ZHANG Jian-ling1, PEN Min1 （1.湖南省电力公司试验研究院，湖南 长沙 410007；2.大唐华银金竹山火力发电分公司，湖南 冷水江417505） （1．Hunan Electric Power Test and Research Institute, Changsha 410007, China； 2. Datang Huayin Jinzhushan Thermal Power Generation Branch Company, Lengshuijiang 417505, China) 摘 要: 大唐华银金竹山火力发电分公司3号锅炉是世界首台600 MW超临界燃用无烟煤的“W”型火焰锅炉机组。投运后锅炉在短时间内连续发生5次高负荷、投自动协调时主蒸汽温度低的问题，造成机组被迫降负荷、甚至停运。其主要原因为：原给水自动策略以磨煤机入口容量风代表煤量计算煤水比，以汽水分离器出口蒸汽焓值作为修正，而风煤比不确定性和焓值代表性不够，给水自动可靠性不高；实际给水自动控制策略选择汽水分离器出口温度作为控制对象，反映比较缓慢，易误判。通过优化现有给水控制策略，在逻辑中设定不同负荷下的给水流量和水冷壁壁温控制值，当启停制粉系统时增加电负荷前馈、减弱煤水比前馈，以及规范操作等措施，解决了这一问题。 Abstract: The No. 3 boiler of Datang Huayin Jinzhushan Thermal Power Co. Ltd, which is the first anthracite 600MW W-shaped flame boiler which is using tangential direct firing system in the world, boiler unit has been a succession of five main steam temperate under subnormal pressure of high load in the period of automatically coordinated control after or before being put into production, this not only makes machine set down the load, even abnormal outage, but also threats safe operation of boiler unit. The main reason for this subnormal pressure is that the original design on feed water control strategy makes enthalpy furnace outlet as its coordination target, but there’s only one pressure in furnace outlet separator, enthalpy is of inadequate representation, low reliability and incomplete concept and separator exports temperature, with its fast changing speed, is forced to be a control target, but it is installed inside a big package of boiler(410℃heat insulation), with low reflection, unable to accurately and timely reflect and judge degree of superheat on main steam temperature, feed water control strategy need to be improved. Through perfecting existing feed water control strategy,