Model Predictive Control Of Soft Constraint In Triangular Interval And Its Application In Cement Rotary Kiln

Cement industry is one of the most important industries in our country at present. The key equipment of the cement industry is the cement rotary kiln. The performance of cement rotary kiln is directly related to the output and quality of cement. The research object of this paper is the research of the cement rotary kiln calcination system, studying the relationship among variables of cement rotary kiln systematically. In view of the existing model predictive control algorithm of defects, from the study on the technology of cement rotary kiln of mechanism analysis, this paper presents a model predictive control algorithm based on triangle interval soft constraint and a model nonlinear predictive control algorithm based on triangle interval soft. The specific research work are as follows:First of all, the basic principle of predictive control algorithm is studied, and the predictive control algorithm is divided into linear model predictive control algorithm and nonlinear model predictive control algorithm. Then analysing the common methods, the study is based on the comparison of linear dynamic matrix control and nonlinear predictive control based on the combination model.Secondly, according to the linear MPC algorithm, a model predictive control algorithm based on triangle interval soft constraint is established. According to the actual needs of the industrial process, the triangular interval is determined according to the tolerance interval and the ideal target value, thereby realizing the priority to control the CV in the triangle. The dynamic optimization was carried out on the CV and CV will be controlled to the ideal target value step by step. The algorithm also increases the degree of freedom of the system and ensures the robustness.Then, based on the nonlinear characteristics and complicated working process of the industrial process, a nonlinear system predictive control algorithm based on the triangle soft constraint is designed. In the prediction of the time domain, the upper and lower bounds of the CV are defined, and then the user-defined constraints are processed to form a triangular soft constraint. It is added to the objective function to optimize the solution, so that the prediction of the output in the future for a period of time tend to set values, to achieve effective control of the program.Finally, the working mechanism of cement rotary kiln is studied in this paper. Selecting appropriate control parameters and using the actual measured data to identify the model, construct BP-ARX combination model as the prediction model, and design a triangular soft constrained structure model predictive controller. The effectiveness of the proposed algorithm is verified by the experimental research on the model predictive controller of the intelligent expert control system in the cement rotary kiln.