Journal of University of Duhok, Vol. 24, No.2 (Pure and Eng. Sciences), Pp 76-89, 2021 76 DESIGN OF A FUZZY CONTROLLER FOR SOLAR PV ARRAY FED WATER PUMPING SYSTEMS RUAA R. SAFAALDEEN and LOKMAN H. HASSAN Dept. of Electrical and Computer Engineering, College of Engineering, University of Duhok, Kurdistan Region- Iraq (Received: August 13, 2021; Accepted for Publication: October 7, 2021) ABSTRACT The purpose of this paper is a designing an efficient solar Photovoltaic Water Pumping System (PVWPS) by using a three phase induction motor. Two adaptive fuzzy logic controllers are proposed to control the dc-link voltage and the induction motor speed. A combination between of fuzzy logic and gain- scheduling controller is proposed to design the adaptive Fuzzy Gain-scheduling Proportional and Integral (FGPI) controllers. A linearized model is considered for the system using small signal model. The performances of the PVWPS using the proposed controllers are set side by side to those gotten from the classic Proportional plus Integral (PI) controllers. The simulation results demonstrated that the suggested controllers are effective in enhancing the dynamic performance of the system. KEYWORDS: Fuzzy logic control, PV system, induction motor, speed control, vector control. 1.1.INTRODUCTION, nergy demand has increased significantly as a consequence of industrialization. The slow depletion of oil and coal has begun. On the other hand, traditional energy generation continues to increase greenhouse gas emissions. Nowadays the global task is reducing emissions of carbon dioxide and ensure safety, producing clean and economical energy, as well as achieving more sustainable energy systems (Santos, Antunes, Chehab, & Cruz, 2006). Researchers have focused their attention on PV systems, which are promising as a good renewable energy source. Because there are no moving parts, solar energy is completely clean. Solar energy requires no maintenance, produces no pollution, and causes no noise (Szabó, 2017; Yu & Chien, 2009). Photovoltaic Water Pumping System (PVWPS) is the most well-known application of PV-based standalone systems, particularly in areas with abundant solar radiation but no connection to national power networks. Induction Motor (IM) is the most existing topologies of Photovoltaic Water Pumping System (PVWPS) for driving the pump due to the lack of a commutator and brushes. Hence, IMs are reliable, cost-effective, and free maintainable. In addition, IMs have light weight, low inertia, high efficiency and overload capacity (Ramesh, Vasavi, & Sirisha, 2014). However, IM, in general, are very nonlinear and have complex time-varying dynamics. As a result, the speed regulation of IM is a complicated matter in industry. For controlling IM, the basic goal is to keep the machine running efficiently and effectively (Krishnan, 2001). Control techniques designed for AC drives and dc-link voltage provide a good chance to use the AC motor in PV systems. Conventional Proportional and Integral (PI) and fuzzy controllers are two controllers that have quite different properties and are both efficient for managing the dc-link voltage and an induction motor speed (Usha & Subramani, 2018). In (Ghosh, Ganesh Malla, & Narayan Bhende, 2015), а model of the small-signal was obtained and a pair of PI controllers were designed to control the speed of IM and to regulate the dc-link voltage. The simulation outcomes clearly showed that the linearized system neatly illustrates the nonlinear system round the same working conditions and PI controllers realize desired performance and robustness. In (Tian, Loh, Deng, Chen, & Hu, 2016), the PI controller achieved the modification of dc-link voltage. A significant improvement in dc helps to make the tracking error stable. IM`s speed control is handled by incorporating non-linear properties, following recent advancements in smart controllers and E