对史密斯预估器的改进

在大延迟系统中 ,史密斯预估器已得到广泛的应用 ,但如果系统动态模型不很理想 ,从系统模型中来的偏差会使控制性能恶化 ,甚至不稳定。因此 ,其应用受到限制。改进型史密斯预估器对原史密斯预估器的不足之处提出了改进的措施 ,使用两个控制器分别对给定量和扰动量进行控制 ,降低了对系统模型精度的要求 ,使系统设计简单 ,控制性能良好。

The Improvement on the Smith Predictor

Smith predictor is used for control of processe with dominant time delay.But if the dynamic process model is not accurate,a deviation from the process model result in a deterioration of the control performance ,or even instability.So its application is limited.An improved Smith predictor is put forward because of the defect of Smith predctor.Two controllers are used to control setpoint tracking and load rejection respectively.The system is insensitive to the model mismatch,and the good performance is obtained.