An Improved Model-free Adaptive Control Algorithm And Its Research In Liquid Level Systems

With the advancement of the times and the development of science and technology,the development of control theory from classic control theory to modern control theory to the integration of artificial intelligence technology today is an important milestone in the history of human scientific and technological progress.This article intends to apply different control algorithms to programmable logic control through a general technical means,to solve the problem of imbalance in the development of control theory and industrial practical applications,and to do a good job in connection to promote the coordinated development of these two aspects.This paper introduces the relevant theories of the liquid level control system in process control,completes the establishment of single and double-capacity water tank control models based on the law of conservation of mass,derives transfer functions and state space equations,and analyzes the working characteristics of the liquid level system.In order to better realize the semi-physical simulation work,the Tank model in the Factory I/O simulation software was used to establish a single-capacity water tank and a dual-capacity water tank scenario,and the effectiveness of the scenario was verified through experiments and theoretical calculations.In view of the problem that control algorithm design in the field of control theory is mostly based on model theory,from the point of view of control theory,the control strategy based on model-free adaptive control in data-driven theory is selected,which is the same as the PID control algorithm in industrial control.Model-free control strategies are simple,intuitive and easy to apply.And fully considering that there are always unpredictable disturbances in the system in practical industrial applications,the idea of linear expansion observer is used,and the idea of auto disturbance rejection is added to the improved control algorithm to improve the robustness of the control algorithm and the ability to eliminate disturbances.Realize the hardware-in-the-loop simulation work based on the Factory I/O model with the help of the digital twin control idea,which includes the technology of Modbus/TCP industrial communication protocol data exchange,ODK₁500S and Target₁500S convert the Simulink controller into the SCL language technology,PLSIM Advance and Mod Scan realizes industrial communication test technology,etc.The semi-physical simulation experiment shows that this scheme can not only shorten the controller parameter debugging cycle,but also reduce the hardware debugging loss,which verifies the practical application significance of digital twin technology.Finally,using the above technical means,the improved LESO-MFAC control algorithm is applied to the programmable logic controller.Through the control comparison and analysis of the actual liquid level system,it shows that the improved model-free adaptive control algorithm proposed in this paper is good its dynamic performance and wide-ranging industrial application value also provide new technical means for theoretical scientific research results to be applied.