Design of a Fuzzy Logic Based Controller for Fluid Level Application

Abstract

In industrial process control, fluid level control is one of the most basic aspects. Many control methods such as on-off, linear and PID (Proportional Integral Derivative) were developed time by time and used for precise controlling of fluid level. Due to flaws of PID controller in non-linear type processes such as inertial lag, time delay and time varying etc., there is a need of alternative design methodology that can be applied in both linear and non-linear systems and it can be execute with fuzzy concept. By using fuzzy logic, designer can realize lower development cost, superior feature and better end product. In this paper, level of fluid in tank is control by using fuzzy logic concept. For this purpose, a simulation system of fuzzy logic controller for fluid level control is designed using simulation packages of MATLAB software such as Fuzzy Logic Toolbox and Simulink. The designed fuzzy logic controller first takes information about inflow and outflow of fluid in tank than maintain the level of fluid in tank by controlling its output valve. In this paper, a controller is designed on five rules using two-input and one-output parameters. At the end, simulation results of fuzzy logic based controller are compared with classical PID controller and it shows that fuzzy logic controller has better stability, fast response and small overshoot.

Performance Comparison of Pid Controller and Fuzzy Logic Controller for Water Level Control With Applying Time Delay

“…In order to obtain high-quality products, the liquid level in the tank must be maintained at a specific point. Since the parameters of the industrial plant change frequently, maintaining the water level at a specific point is difficult (Shahid et al, 2016). For this reason, the liquid level control system is considered a complex system that traditional control methods are insufficient to deal with (Yumurtacı and Verim, 2020).…”

“…Therefore, using the FL controller was suggested as a solution to overcome these problems (Dinesh et al, 2015). Many studies made a comparison between the performance of the FL controller and the PID controller in terms of maintaining the level of liquid in a tank, and they found that the FL controller has better stability, smaller overshoot, and fast response (Shahid et al, 2016) (Thakur et al, 2015) (Prusty et al, 2014) (Yahya et al, 2020). Others tested the performance of PID and FL controllers in coupled tank systems and found that FL controller has better performance, and it is a good option for real-world applications (Kumar and Nagpal, 2017).…”