PERFORMANCE COMPARISON BETWEEN FUZZY CONTROLLERS AND PROPORTIONAL CONTROLLERS

The aim of this work is to compare the performance of two fuzzy controllers and a proportional controller. The controlled variable is the level of a tank with gravity discharge. For the study, a dynamic simulator was developed and implemented in Simulink (R) of MATLAB (R). For each studied controller, the response produced by a step change in the set point was evaluated. To make a valid comparison, the controllers were adjusted to produce equal offsets. The results show that systems based on heuristics (fuzzy controllers) can be as or more convenient than those based on deterministic knowledge (the proportional controller). Although the proportional controller acts at a higher speed, fuzzy controllers improve the values of some of the most important performance rates, such as the overshoot, oscillations and ripple factor.