Mehdi Shafiei - Department of Electrical Engineering, Majlesi Branch, Islamic Azad University, Isfahan, Iran
Amir Hossein Zaeri - Department of Electrical Engineering, Shahinshahr Branch, Islamic Azad University, Shahinshahr, Iran

Water level controlling has a wide range of applications in various fields, such as liquid storage tanks, feed tanks, product tanks, intermediate buffer containers, boilers and other equipment. The aim of this study is examining two separate fuzzy control systems and PID for controlling the level of three storage tanks in series in two different states.[6] First, we consider stability of PID controller for the single state and then we examine the PID for the cascade state. After that, we compare the time response specifications. For the next stage, we consider the two previous states for the fuzzy controller, and by the end, we compare the fuzzy and PID responses with each other.[1,2]

P-I controller, PID controller, Fuzzy logic controller, Ziegler-Nichols method, Simulink, Level control, Single loop, Cascade Loop, conversion function