(IJACSA) International Journal of Advanced Computer Science and Applications, Vol. 8, No. 3, 2017 165 | Page www.ijacsa.thesai.org Improving the Control Strategy of a Standalone PV Pumping System by Fuzzy Logic Technique Houssem CHAOUALI (*) , Hichem OTHMANI, Dhafer MEZGHANI, Abdelkader MAMI UR-LAPER, Faculty of Sciences of Tunis, University of Tunis El Manar 2092 Tunis, Tunisia Abstract—This work aims to develop an accurate model of an existing Photovoltaic Pumping System (PvPS) which is composed of an Ebara Pra-0.50T Asynchronous Moto-Pump (AMP) fed by Kaneka GSA-60 photovoltaic panels via a Moeller DV-51 speed drive. The developed model is then used to compare the performance of the system with its original control strategy based on classical indirect vector control strategy using PI speed controller and the proposed new control strategy based on Fuzzy Logic control technique for speed control and MPPT system. The obtained results of comparative simulations, induced in different dramatic variation of working conditions, show that the developed control strategy brought major enhancements in system performance. Keywords—Photovoltaic Pumping System; Asynchronous Moto-Pump; PI Speed Controller; Fuzzy Logic Control Technique; MPPT Tracking System; Simulation I. INTRODUCTION Air pollution problems and its disastrous consequences mainly caused by increasing consumption of conventional energy sources such as gas, oil and coal, has encouraged scientific society towards developing environmentally friendly energy sources which are mainly extracted from renewable energy sources such as the sun, water, wind… etc. Among these new energy sources, and thanks to its continuous technological progress and manufacturing cost reduction, Photovoltaic (PV) energy presents one of best choices from different existing renewable energy sources. PV technologies are widely used for numerous and various types of applications [1,2]. For some countries, especially where agriculture is an important economic engine such as Thailand [3], pumping water using PV generator (PVG) is a practical solution for rural development where water demand for irrigation and domestic use, is increasing. PV pumping importance is related to the fact that these rural areas are generally without electricity supply sources. [4] In these cases, different types of PV pumping systems have rapidly replaced traditional pumps such as diesel and gasoline pumps especially that these developed new technologies help to avoid the need for maintenance personnel and fuel supply problems [5]. Despite these different advantages, the generated PV power is strongly dependent on weather conditions especially solar irradiation which contributes constantly in rapid variation of I-V and P-V characteristics of the PVGs [6]. This fact might explain the totally degraded performance that was found in early stage of PV pumping application in comparison with same pumping systems once supplied with a constant voltage source. Trying to fix this problem, later studies suggested that using a DC/DC converter as an adaptation between the load and the source guaranties major improvements in the used motor characteristics as well as the generated power from the PVG [7]. Therefore, researches have been focusing on developing different algorithms and techniques to be used in computing the optimal duty cycle of the DC-DC converter to ensure the better tracking of the Maximum Power Point (MPP) continuously in spite of irradiation variations [8]. In another hand, it is known that different types of disturbances, intern or extern, heavily influence the dynamic performance of several industrial systems such as power systems [9]. In this context, different types of controllers have been introduced over the years. But unlike conventional controllers, Fuzzy Logic (FL) controllers have proved better efficiency in different industrial processes thanks to its robustness. Thus, this reality made us think to apply an upgrade, by using the FL technique, of the existing control strategy of a Photovoltaic pumping system. [10] This paper gives in a first place a general overview of the system where its different blocks are presented and modeled separately:  The model of the PV generator which is composed by Kaneka GSA-60 PV panels.  The model of the 3 phased digital speed drive inverter which is a Moeller DV51 type.  The model of the 3 phased asynchronous machine and the trained centrifugal pump which both form the studied moto-pump type Ebara Pra-0.50T. Then, the next section presents is reserved for presenting the actual control strategy and the upgraded one. In this part, we give a general presentation of the Fuzzy Logic technique and how we deployed different FLCs in the system in order to improve its control strategy. In the last section, we present several results comparing the behaviour of the pumping system with and without the developed FL control strategy and the major proved enhancements in performance.