Research On Tuning Of The Parameters Of The Smith Predictor And Its Application

Smith Predictor control is designed for the delay system,which can effectively compensate for the delay of the control process,which can be used to achieve good results when the object is delayed for a long time.In actual production,it is applied to many aspects for its clear physical meaning.The Smith Predictor has the ability to translate a delay into a non-delay when the Smith predictor matches the object.However,due to the parameters change in reality,Smith predictor can not always match the object,the system's robustness and anti-interference ability also have some problems.In this paper,we study the control effect of the delay system when the Smith predictor and the object parameter mismatch.Through the theoretical derivation and application of Matlab,the Smith Predictor parameter tuning formula is obtained.The setting formula is applied to the general delay system and the large delay superheated steam temperature control system.The simulation results show that the parameterized Smith predictor has better control effect on the delay system with better robustness.The main contents of the article are as follows:First of all,introduce the control and improvement strategies of delayed systems at home and abroad.Then,the Smith predictor control and its compensation principle are introduced.Since the object parameters are time-varying,tuning the Smith predictor parameters to improve the control effect of the system is very necessary.Integral square error(ISE)and integral time square error(ITSE)are respectively used as performance indexes to optimize the parameters of Smith predictor.If 0.901(27)K?(27)4,the predictor parameters could be set.If K??0.901,system performance adjusted with negative predictor gain or PI controller.If K??4,the system is more sensitive to changes in the parameters of the predictor,so that the parameters of the estimator and the object can be matched.K?represents the normalized value of the product of Proportional Gain(k_c),Static Gain(k_p),and Delay(?_p).Finally,the Smith predictor parameter tuning method is applied to the general delay system and the large-delay superheated steam temperature system,and the simulation results show that the performance and robustness of the control system have been improved.The results show that the setting formula is very effective.