基于延迟抑制控制结构的主蒸汽温度控制

摘要

针对发电机组主蒸汽温度被控对象纯迟延、时变、不确定的特性，基于误差分析，提出了一种基于延迟抑制控制结构的主蒸汽温度控制策略，将基于非精确模型的闭环输出和系统实际输出加权作为冲量构成新型的控制结构，并将其与 Smith 预估补偿器相结合形成复合控制结构，从理论上分析了复合控制结构的鲁棒性。在机组负荷分别为37％、50％、75％、100％4种工况下，将复合控制结构与Smith 预测补偿控制结构进行仿真比较。结果表明，采用复合控制结构解决了模型参数小范围时变问题，复合控制结构阶跃响应的控制效果明显优于Smith预测补偿控制结构，提高了系统抗迟延性能。%Against such characteristics as pure time delay,time-varying and uncertainty of the controlled ob-j ect in main steam temperature control,a new control strategy based on anti-delay control structure was proposed,on the basis of error analysis.The inexact model based close-loop output and the actual close-loop output were weighted as a new structure's impulse.The new structure and the Smith predictor were com-bined to form a composite structure.The robust performance of the composite structure was analyzed.In addition,control effect of the composite control structure and the Smith predictive compensate control structure was compared.The results show that,the composite control structure solved the problem of time-varying within a small range,and its control effect to step response was obviously superior to that of the Smith predictive compensate control structure,which improved the anti-delay performance of the system.