先进预测控制在SCR控制系统中的运用  

Application of Model Predictive Control in SCR Control System

作　　者：叶蒙双 冯晓露[1] 张政江[1] 

机构地区：[1]浙江大学能源工程学院,杭州310027

出　　处：《科学技术与工程》2016年第10期155-158,共4页Science Technology and Engineering

摘　　要：某电厂#3机组为330MW亚临界参数汽包炉,脱硝系统采用SCR脱硝控制。目前现场对脱硝氨气流量控制采用固定摩尔比控制方式,即通过控制脱硝效率来保证出口NO_x浓度。在实际运行中,存在着脱硝效率波动大,出口NO_x偶尔超标的情况。结合该电厂的某段时间里的运行数据,利用模型辨识技术,建立SCR系统仿真模型,分别采用先进预测MPC控制和常规PID控制,对比两种控制状态下的出口NO_x,得出MPC控制优于PID的结论。再依次改变摩尔比,以每小时出口NO_x的平均值不高于90 mg/m^3为上限,对比两种控制状态下,得出在MPC控制下,出口NO_x的波动范围小且超标数较低。In some plant unit 3 is a 330 MW Power Plant Unit parameter subcritical drum furnace,and it uses SCR technology in denitration system.Currently the unit uses constant molar ratio method to control the ammonia flow,which also means ensure the outlet NOxconcentration by controlling denitration efficiency.However,in actual operation,it exits some problems like denitration efficiency fluctuation,excessive NOxoccasionally and so on.Combined with a certain time of the plant＇s operational data,mathematical model of SCR is built by using the model identification technology,and then compare the outlet NOxrespectively controlled by MPC and PID strategy in simulation,we draw the conclusion that using MPC controller is better than PID.And then to change the molar ratio,setting the average outlet NOxper hour upper limit 90 mg / m3,the two control strategies were compared,and that also can beseen that MPC can get better result in exceed hours and fluctuation.

关 键 词：SCR 先进预测MPC控制 常规PID控制 固定摩尔比 

分 类 号：TK323[动力工程及工程热物理—热能工程]