一种改进的测量双背压低压缸效率的算法与误差分析  

An Improved Algorithm and Error Analysis for Measuring the Efficiency of Double Back Pressure LP Cylinders

作　　者：朱宝 董益华 梅益铭 华敏 顾伟飞 ZHU Bao;DONG Yihua;MEI Yiming;HUA Min;GU Weifei(Zhejiang Provincial Key Laboratory of Energy Conservation&Pollutant Control Technology for Thermal Power(Zhejiang Energy Group R&D),Hang Zhou 311121,Zhejiang Province,China)

机构地区：[1]火力发电高效节能与污染物控制技术研究浙江省重点实验室(浙江浙能技术研究院有限公司),浙江省杭州市311121

出　　处：《中国电机工程学报》2020年第16期5274-5281,共8页Proceedings of the CSEE

摘　　要：大型火力发电机组一般至少配置2个低压缸,将2个低压缸作为一个整体来测量其平均效率是当前验收试验中常规算法。当2个低压缸排汽容积流量存在差异时,该算法会引起计算误差,某些工况可达0.5%以上。提出一种改进的测量双背压低压缸效率的算法,综合应用厂家设计数据、验收试验中测量数据,可分别计算2个低压缸效率,计算误差根据来源可分为2个低压缸效率测量值均值的误差及差值的误差。通过分析与厂家设计数据对比结果、验收试验中应用结果,验证了算法精度与稳定性。验证结果表明:改进算法计算低压缸A、B效率均值的误差及差值的误差可控制在0.1%左右,可通过减小排汽压力差值来减小低压缸A、B效率测量值差值的误差。Large thermal power generation unit was generally equipped with two low pressure(LP) cylinders at least. The two LP cylinders were taken as a whole to measure the average efficiency in the conventional method. It could cause calculation error when the volume flow of exhaust steam of the two LP cylinders was different, which can reach more than 0.5% under some conditions. In this paper, an improved algorithm for measuring the efficiency of double back pressure LP cylinders was proposed. According to the manufacturer’s design data and measured data of acceptance test,it could calculate the efficiency of two LP cylinders separately. The calculation error of the improved algorithm could be divided into mean value error and difference value error of efficiency measurements of the two cylinders according to the error source. The accuracy and stability of improved algorithm was verified by analyzing comparison results with manufacturer’s design data and application results in the acceptance test. The verification result shows that the mean value error and difference value error of LP A and LP B cylinders’ efficiency measurements calculated by the improved algorithm can be controlled in 0.1%. The difference value error can be reduced by diminishing the exhaust pressure difference of LP A and LPB cylinders.

关 键 词：低压缸效率 双背压 效率测量 汽轮机 

分 类 号：TK261[动力工程及工程热物理—动力机械及工程]