循环流化床锅炉燃烧系统动态特性的分析

Dynamic Analysis of Combustion System of CFB Boiler

为了克服传统方法存在的分析相对误差率高和分析时间较长的问题,文章提出了一种新的基于经验模态分解的循环流化床锅炉燃烧系统动态特性分析方法。以循环床锅炉流动参数和热力参数为基础沿炉膛高度方向对炉膛区域进行划分,并构建循环床锅炉燃烧系统数学模型。根据建模结果,利用经验模态分解方法对热量信号进行分解,并对每一个IMF分量进行希尔伯特变换,得到希尔伯特谱。以希尔伯特谱为基础,分析主蒸汽压力、床温、燃烧系数等参数变化情况下,热量信号的阶跃响应,得到最终的燃烧系统动态特性分析结果。实验结果表明,该方法的热量信号去噪效果好,分析相对误差率平均值为3.6%,分析时间始终保持在0.6 s以下。

The traditional method has the problems of high relative error rate and long analysis time.A dynamic characteristic analysis method of circulating fluidized bed boiler combustion system based on empirical mode decomposition(EMD)is proposed.Based on the flow parameters and thermal parameters of the circulating bed boiler,the furnace area is divided along the height direction of the furnace,and the mathematical model of the combustion system of the circulating bed boiler is established.The EMD method is used to decompose the heat signal and obtain the Hilbert spectrum.The step response of the heat signal is analyzed when the main steam pressure,bed temperature,combustion coefficient and other parameters change,and the dynamic characteristics of the combustion system are obtained.The experimental results show that the denoising effect of this method is good,and the average relative error rate is 3.7%.