Research on Liquid Level Control System of Multi-capacity Water Tank

Abstract

With the development of process control field, liquid level control system is more and more widely used. Based on the analysis of the liquid level characteristics and the coupling characteristics of the upper water tank to the lower water tank, this paper designs a conventional control scheme. For the complex liquid level control system with nonlinearity and large delay, it is difficult to establish an accurate mathematical model, so it can not meet the requirements of complex control system. Combining the advantages of fuzzy control and decoupling control, a fuzzy decoupling control scheme is designed in this paper. In MATLAB simulation, three control schemes including conventional control, conventional decoupling control and fuzzy decoupling control are applied to the coupling effect between upper and lower water tanks in multi-capacity water tanks. The conventional control is the traditional PID control, the conventional decoupling control is achieved by using the decoupling coefficient method, and the fuzzy decoupling control is a control scheme that adjusts the parameters of the designed fuzzy decoupling controller to obtain the optimal control effect. Finally, the three control schemes are compared through the obtained curves.