随着我国太阳能、风能等发电装机容量的迅速增长,电网对火电机组的调峰需求越来越高,火电机组运行呈现负荷波动大、频率高的特点。为研究火电机组的动态特性,本文以某600 MW超临界燃褐煤直流锅炉为例,建立了系统主要热力设备的动态模型,进而研究获得了这些设备的动态特性。结果表明,各设备在系统中的位置、作用各不相同,其动态特性也有差异。以响应时间为例,省煤器、回转式空预器和制粉系统的动态响应时间最长,约700 s以上,其次是水冷壁、过热器和再热器,约400 s,泵与风机的动态时间很短,在研究机组的动态过程时可以忽略。
With rapid rise of solar and wind power capacity,power network is urgent in need of peak regulation capacityof thermal plant And thermal plant presents characteristic of large amplitude and high-frequency load fluctuation.Simulation models of a 600 MW supercritical lignite-fired once-through boiler were developed with GSE software.The dynamic operation process of thermal componentsin the boiler system,such as water wall,economizer,superheater,reheater,pulverizing system,air preheater,and pump and fan are simulated.It is found that the dynamic characteristics of thermal components are different due to the differences in install positions and functions.For example,the response time of economizer,pulverizing system and air preheater for the disturbance are longer than that of other thermal components.It can last more than 700 seconds.For,water wall,superheater,or reheater,the response time is about 400 seconds.For the pump and fan,the timeof dynamic process can be neglected when compared with other components.