电站煤粉锅炉炉内压力波动的非线性特性分析  

Analysis of the Non-linear Characteristics of In-furnace Pressure Fluctuations of a Pulverized-coal-fired Utility Boiler

作　　者：牛蔚然[1] 邱燕[1] 田茂诚[1] 刘志超[2] 

机构地区：[1]山东大学能源与动力工程学院,山东济南250061 [2]山东电力研究院热能研究所,山东济南250021

出　　处：《热能动力工程》2009年第4期457-460,共4页Journal of Engineering for Thermal Energy and Power

基　　金：国家重点基础研究发展规划基金资助项目(2007CB206900)

摘　　要：电站燃煤锅炉炉内过程是一个复杂的非线性时变过程,因此在传统的线性分析技术基础上引入非线性分析方法具有一定的现实意义。通过对可反映炉内瞬态过程的炉内压力信号的统计检验分析,确定炉内压力波动序列分布不服从正态分布,而是服从具有尖峰胖尾特性的分形分布;多变量影响造成的不可预测的压力间断性跳跃,是炉内压力波动服从分形分布特征的根本原因。利用最大拟然估计方法对压力波动的分形分布参数进行了估算,计算表明炉内压力波动信号的方差无统计意义。利用经典的R/S统计分析工具,计算得到炉内压力波动序列的Hurst指数,分析了炉内压力波动情况与其Hurst指数间的关系,这可为锅炉燃烧优化调整提供有益的指导。The in-furnace process of pulverized-coal-fired utility boilers is a complex non-linear time-dependent one.As a result,to introduce a non-linear analytic method on the basis of the traditional linear analytic technologies is of definite realistic significance.Through a statistical inspection and analysis of the in-furnace pressure signals which are capable of reflecting the in-furnace transient process,it has been determined that the in-furnace pressure fluctuation sequence distribution assumes a fractal one featuring a pointed peak and a wide tail instead of a normal distribution.The unpredictable intermittent leap of pressure caused by the influence of multiple variables constitutes the root cause of the in-furnace pressure fluctuations complying with fractal distribution characteristics.By utilizing the maximal likelihood estimation method,estimated were the fractal distribution parameters of the pressure fluctuation.The calculation results show that the variance of the in-furnace pressure fluctuation signals is of no statistical significance.By using the classic R/S statistical tool,the Hurst exponent of the in-furnace pressure fluctuation sequence was calculated and the relationship between the in-furnace pressure fluctuation condition and the Hurst exponent,analyzed.The foregoing can provide useful guidance for the optimization and adjustment of combustion in boilers.

关 键 词：煤粉锅炉 压力波动 分形分布 HURST指数 

分 类 号：TM623.94[电气工程—电力系统及自动化]