用简单换热器模型实现SIS的核心功能

Realization of SIS core functions with simple heat exchanger model

汽水系统工质流量的测量技术是制约提高实时发电煤耗计算精度的主要原因之一,也是制约厂级监控信息系统(SIS)核心功能实现的主要技术障碍。简单换热器模型可利用换热器进、出口温度和压力计算工质流量,能在可比较条件下评价换热器的传热性能。现场试验表明,以校验后的流量表为比较基准,简单换热器模型的计算流量偏差不大于±1.5%;仿真试验数据表明,用简单换热器模型计算污垢热阻的误差不超过±3.2%。因而可使用简单换热器模型开发运行经济指标计算模型、吹灰优化控制系统、换热器性能诊断平台等优化运行软件,实现SIS的核心功能。工程试验表明,以ASME标准试验结果为基准,简单换热器模型计算的发电热耗误差不大于±2.5%。

The measuring technology for working medium flow of steam water system is a major limiting factor for calculation accuracy of real-time coal consumption rate in thermal power plant and also the technical obstacle for the realization of SIS core functions. The simple heat exchanger model calculates the flow with inlet and outlet temperature and pressure of heat exchanger and evaluate the exchanger performance comparably. The field test shows that the flow error calculated by simple heat exchanger model is within ＋-1.5% with the calibrated flow meter as comparing baseline. According to the simulation results, the calculation error of heat resistance is no more than ±3.2%. Therefore, this model can be used in the development of operation optimization software such as economic index calculation, soot blowing optimization system, heat exchanger management platform etc. to realize the core functions of SIS. Project test shows that comparing with the experimental results of ASME standard, the heat consumption error calculated by simple heat exchanger model is no more than ±2.5%.