发电厂脱硫系统二氧化硫排放量适应性控制方法研究

Study on Adaptive Control Method of Sulfur Dioxide Emission in Desulfurization System of Power Plant

在发电厂脱硫生产pH值控制过程中,运用MATLAB软件对过程控制进行系统辨识,建立控制系统的数学模型,把求得的数学模型应用于SMITH预估器的设计,在实际运用中取的良好的效果。设计目标随动的变参数自适应SMITH控制系统调节系统能及时以脱硫吸收塔出口二氧化硫折算值改变pH值设定值适应各种工况的变化,在保持稳定的二氧化硫脱除率情况下进一步调高调节系统响应的快速性,在稳定工况下提高石灰石浆液的利用率,提高脱硫运行的经济性。

In view of the pH value control in the process of desulfurization slurry supply in power plant,the mature least square program in MATLAB is used to identify it,and the mathematical model of slurry pH value control system in absorption tower is established.The obtained mathematical model is applied to the design of SMITH predictor,and good results are obtained in practical application.The variable parameter self-adaptive SMITH control system with design target follow-up can change the pH value setting value in time with the sulfur dioxide conversion value at the outlet of desulfurization absorption tower to adapt to the changes of various working conditions,further improve the response rapidity of the adjustment system while maintaining stable sulfur dioxide removal rate,improve the utilization rate of limestone slurry under stable working conditions,and improve the economy of desulfurization operation.