火电机组过热器压力和温度的动态研究

Pressure and Temperature Dynamics in Power Plant Superheater

基于过热蒸汽比焓和密度的双线性拟合函数,用机理分析法建立了一段过热器集总参数的压力和温度的动态模型。研究表明:该模型能够反映在机组负荷变化范围大的工况下过热系统的主蒸汽压力和温度的动态特性,以及受到减温喷水量或主汽门调门开度扰动时,主蒸汽压力和温度的耦合动态响应。此外,用辐射能信号的函数替代过热器的有效吸热量并结合火电机组的其他实测数据可以对所建模型进行对比验证。

Based on the physical principles and the bilinear fit functions of the enthalpy and density of superheated steam, a lumped parameter model of a section of super-heater was developed. It is shown that the model can capture the dynamical properties of the pressure and temperature at throttle valve over a large plant load varying range, and the coupling responses of them while regulating spraying water flow rate or tuning throttle valve position. In addition, the model can be validated by using radiation energy signal in place of heat absorption of the super-heater and other data gathered form an actual plant.