Liquid Level Control Of A Three-tank System

Multiple flow system has been widely used in the modern agriculture,industry,chemical industry,oil and other important areas,such as boilers,oil storage tanks,rectifying columnands so on.These objects are oftentime-varying,strong coupling,nonlinear,multiple input and multiple output.As the aging equipment the system leakage may occur.Three-tank system can simulate complex multiple flow system,and has a broad application prospect.In this paper,two control methods of Three-tank system are carried on the detailed research.This article mainly has carried on the following several aspects of research:Study of threetank system including the mathematical mode,the simulation model is established in Matlab/Simulink.Describe the control objectives of Three-tank system according to the characteristics.Researchon Constrained H_?Output Feedback control method.Applied the control method to the Three-tank system,the system can trackthe target levels,deal with the leakages,and satisfy the control input constraints.Research on Disturbance Obersver Based Control method(DOBC).Applied the control method to the Three-tank system,the system can track the target levels,deal with the leakages,high-order unmodeled dynamics and parameter perturbation.In this paper,the simulations and physical experiments of DOBC and Constrained H_?Output Feedback control method are carried out,the results show that these two methods are effective.In addition,considering the Three-tank system tracking changing liquid levels,control methods based on Differential Flatness,Polyhedron and repeatedly solve the controller are also researched.The feasibility is discussedthrough simulations and analysis.