循环流化床锅炉煤泥加入控制系统优化

Control System Optimization for Adding Coal Slurry into Circulating Fluidized Bed Boiler

针对某电厂2×300 MW亚临界循环流化床(CFB)锅炉新建煤泥加入系统投运后,其控制系统在煤泥加入量测量、热工保护和自动控制等方面存在设计功能不完善等问题,采取措施:通过实验的方法,测得了在不同加入量下对应的煤泥量,为机组实现燃烧自动控制提供了保障;控制系统增加锅炉主燃料跳闸(MFT)动作停止煤泥泵连锁保护、辅机故障减负荷(RB)动作停运煤泥泵的控制功能及相应的控制逻辑优化;主机分散控制系统(DCS)引入煤泥加入控制系统重要参数;将煤泥加入量引入直接能量平衡协调控制方案并进行了控制逻辑优化。通过优化提高了煤泥加入控制系统的可靠性,完善了机组控制系统的功能。

For a 2×300 MW subcritical circulating fluidized bed(CFB) boiler of a power plant,after the new coal slurry is added to the system,the control system has imperfect design functions in terms of coal slurry addition measurement,thermal protection and automatic control.The countermeasures are as follows: through the experimental method,the corresponding amount of coal mud under different loadings is measured,which supports the automatic control of the unit.The control system increases the main fuel trip(MFT) of the boiler to stop the coal slurry pump chain.The control logic optimization of the coal slurry pump for protection and auxiliary machine failure reduction(RB) operation is performed.The host distributed control system(DCS) introduces the important parameters of the coal slurry into the control system.The coal slurry addition amount is introduced into the direct energy balance coordinated control system and it is also optimized for control logic.Through the optimization,the reliability of the control system for adding coal slurryis improved,and the function of the unit control system is improved.