Many Cans Of Liquid Level Modeling And Energy Shaping Control Hamiltonian System

Multiple-tank liquid level system has the properties of apparent nonlinearity、large inertia and time-delaying. The above properties make the multiple-tank liquid level system a good research platform for various control algorithms and guidance for liquid level system research in industrial manufacturing sector. Multiple-tank liquid level system is in cascaded form; knowing from the hydromechanics, in turbulent conditions, the liquid is nonlinear to the flow rate, which makes control system and its precise control of the three-tank liquid level system more difficult.In recent decades, a multitude of control algorithms, such as PID control, feedback linearization control, sliding mode control, predictive control, intelligent control, are widely applied in laboratory experiment and industrial manufacturing. In recent years, the algorithm of interconnection and damping assignment passivity-based control has received tremendous attention.Along with the development of nonlinearity theory, a novel method of port-controlled Hamiltonian (PCH) system modeling and interconnection and damping assignment control receive tremendous attention. The main feature of this method is that, it represents controlled system in PCH structure, utilizes the interconnection and damping assignment and energy-shaping principle to simplify the design of the controller and make the stability analysis easier. Referring to the SUPCON AE2000liquid level control laboratory platform, this article designs a multiple-tank liquid level control system applying PCH system and interconnection and damping assignment control principle.Firstly, the research development of the multiple-tank liquid level system and its application status quo are summarized, home and abroad, including hardware and software; moreover, various control algorithms and their respective applications are reviewed. Secondly, the basic principles of port-controlled Hamiltonian (PCH) system modeling and interconnection and damping assignment control are provided, including passivity, dissipation and so forth. Also, port-controlled Hamiltonian (PCH) system、 energy-shaping principle、matching method and its corresponding realization and stability analysis are presented. Thirdly, research on the controlled object, cascaded two-tank system, cascaded three-tank system, multiplex four-tank system are accomplished; the controlled object is mathematically modeled with principle modeling method. Then the mathematic model is translated into PCH model and the proper corresponding Hamiltonian function is finely select. Fourthly, the equilibrium point of the two-tank, three-tank and four-tank system are respectively determined; the PCH controller based on energy-shaping method is ultimately obtained; integral control is introduced in order to eliminate the static error. Fifthly, the configuration and the structure of the SUPCON AE2000system is introduced; in the circumstance of MABLAB/Simulink. the proposed controller is testified, the simulation results are satisfactory in dynamical and steady performance; experiment test are also carried out based on the laboratory experiment platform SUPCON AE2000,the controller with integral control is proved to effective; furthermore, in the contrast between the traditional Proportion-integration(PI) control and the PCH controller, the proposed PCH control excels at various aspects, especially in eliminating disturbances.At last, the research work in the paper is summarized, the flaws requiring improvement and the possible main research work in the future are discussed.The proposed modeling and control methods achieve satisfactory results with effectivity; meanwhile, they provide a potential idea for the other control methods applied on multiple-tank system. Moreover, if improved furthermore, the proposed method can be put into industrious process control.