Performance comparison between PI digital and fuzzy controllers in a level control system


Liquid level systems are important in many industrial and academic applications, so measurement and control systems need to be as accurate as possible for this process. However, a level system has a nonlinear dynamic which increases the difficulty of modelling and design controller by classical methods. In order to address these issues, this paper discusses the modeling of a nonlinear level plant and the implementation of strategies for PI control and fuzzy control. The control algorithms are embedded in an 8 bits microcontroller, which provides the plant sample data via serial communication. Response specifications are stipulated so that the performance of the controllers is evaluated and compared. The results show a better performance for the fuzzy controller which could avoid larges overshoots with low computation costs and none anti-windup strategies.


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How to Cite
VASCONCELOS, Felipe José de Sousa; MEDEIROS, Cláudio Marques de Sá. Performance comparison between PI digital and fuzzy controllers in a level control system. Journal of Mechatronics Engineering, [S.l.], v. 2, n. 3, p. 10 - 18, nov. 2019. ISSN 2595-3230. Available at: <>. Date accessed: 08 dec. 2019. doi: