Conventional control system adopts PID controller which cannot well adapt to non-linearity, parameter variation, disturbance and change of objective architecture. To strictly limit the overshoot, using fuzzy control we can achieve great control effect. By using fuzzy logic, designers can realize lower development costs, superior features, and better end product performance. The only reasons are faster and cheaper. The Fuzzy control is very much useful for controlling the tank level of the liquid. The purpose of this setup is to design a simulation system of fuzzy logic controller for liquid level control by using Fuzzy Logic Toolbox and MATLAB Simulink software. Thats why in this paper, an attempt is made to compare the control effect due to fuzzy control and conventional PID control and by comparing we will see that fuzzy control is superior to PID control. Result shows that the fuzzy control gives more concentration to different parameters, such as the time of response, the steady state error and overshoot.

Level transducers, Control loop, Control system, Process control, Conventional controller, Crisp set, Fuzzy set, Fuzzy logic controller

[1] Rem Langari, “Past, Present and Future of Fuzzy Control: A Case for Application of Fuzzy Logic in Hierarchical Control”, IEEE, 1999, pp.760-765.
[2] Chuen Chien Lee, “Fuzzy Logic In Control Systems i.e, Fuzzy Logic Controller”, IEEE Transactions on Systems, man and cybernetics, Vol 20, No.2, March/April 1990.
[3] J.Y.M. Cheung, A.S. Kamal,” Fuzzy Logic Control of Refrigerant Flow”, UKACC International Conference on Control „96, Conference Publication No. 427, 2-5 September 1996.
[4] H. Berenji, “Fuzzy Logic Controllers, in An Introduction to Fuzzy Logic Applications in Intelligent System”, Editors R. Yager, L. Zadeh, Kluwer Academic Publishers, 1992, p. 69-96.
[5] S. Boverie, B. Demaya, A. Titli, “Fuzzy Logic Control Compared with Other Automatic Control Approaches”, 30th IEEE-CDC, Conf. on Decision and Control, Brighton, Dec. 1991.
[6] P.Ramanathan, Sukany A.K.C,S. Mishra, S. Ramasamy” Study on Fuzzy Logic and PID Controller for Temperature Regulation of a System with Time Delay”, IEEE, 2013, pp.274-277.
[7] Sahil Chandan, Rahul Agnihotri,” Fuzzy logic Controller for Flowing Fluids”, International Journal of Advanced Research in Computer Engineering & Technology, Volume 1, Issue 4, June 2012.
[8] Dharamniwas, Aziz Ahmad, Varun Redhu, Umesh Gupta,” Liquid Level Control By Using Fuzzy Logic Controller”, International Journal of Advances in Engineering & Technology, July 2012.
[9] Davood M. Souran, S. H. Abbasi, F. Shabaninia ,” Comparative Study between Tank’s Water Level Control Using PID and Fuzzy Logic Controller”, Springer,Advances in Intelligent Systems and Computing ,Volume 195, 2013, pp 141-153.
[10] Timothy J. Ross. Fuzzy Logic with Engineering Applications. McGraw Hill, 1995.
[11] Considine, Douglas M. Process/Industrial Instruments and Controls Handbook. (McGraw Hill, 1999).
[12] Liptak B.G. (Ed.), Instrument Engineer’s Handbook (CRC Press, 2006).
[13] Mary, P.M., Marimuthu, N.S., "Design of Self-Tuning Fuzzy Logic Controller for The Control of An Unknown Industrial Process," Control Theory & Applications, lET, Vpl.3, No.4, 2009 pp.428-436.
[14] Venugopal P, Ajanta Ganguly, Priyanka Singh,” Design of Tuning Methods of PID Controller Using Fuzzy Logic”, International Journal of Emerging trends in Engineering and Development Issue 3, Vol.5, September,2013.
[15] Farhad Aslam and Gagandeep Kaur. Article: Comparative Analysis of Conventional, P, PI, PID and Fuzzy Logic Controllers for the Efficient Control of Concentration in CSTR. International Journal of Computer Applications 17(6):12-16, March 2011.
[16] Srinivas, P.; Prasada Rao, P. Durga,” Comparative Analysis of Conventional PID Controller and Fuzzy Controller with Various Defuzzification Methods In A Three Tank Level Control System”, International Journal of Information Technology, Control & Automation, Vol. 2 Issue 4, 2012, pp.75-86.