Copyright © 2012 IUG. The 4 th International Engineering Conference –Towards engineering of 21 st century 1 TWO AXES SUN TRACKER USING FUZZY CONTROLLER via PIC16F877A Mohammed S. El-Moghany 1 , Basil M. Hamed 2 1: Master Electrical Eng. Dept., IUG, Palestine: elmoghany@hotmail.com 2: Associate Professor Electrical Eng. Dept., IUG, Palestine: bhamed@iugaza.edu ABSTRACT: This paper presents sun tracking generating power system designed and implemented in real time. A tracking mechanism composed of photovoltaic module, stepper motor, sensors, input/output interface and expert FLC implemented on PIC, that to track the sun and keep the solar cells always face the sun in most of the day time. The proposed sun tracking controller is tested using Matlab/Simulink program, the results show that the controller have a good response KEYWORDS: Fuzzy Logic Control, Sun Tracking, Photovoltaic System, PIC16F877A. I. INTRODUCTION Renewable energy sources play an important role in electric power generation. There are various renewable sources which used for electric power generation, such as solar energy, wind energy, geothermal etc [1]. Solar Energy is a good choice for electric power generation, since the solar energy is directly converted into electrical energy by solar photovoltaic modules [2]. These modules are made up of silicon cells [3]. Many such cells are connected in series to get a solar PV module. The current rating of the modules increases when the area of the individual cells is increased, and vice versa. When many such PV modules are connected in series and parallel combinations we get solar PV arrays, that suitable for obtaining higher power output. The applications for solar energy in recent years are increased rapidly, and that need to improve the materials and methods used to harness this power source [4]. Main factors that affect the efficiency of the collection process are solar cell efficiency, intensity of source radiation and storage techniques. The efficiency of a solar cell is limited by materials used in solar cell manufacturing. It is particularly difficult to make considerable improvements in the performance of the cell, and hence restricts the efficiency of the overall collection process. Therefore, the increase of the intensity of radiation received from the sun is the most attainable method of improving the performance of solar power. There are three major approaches for maximizing power extraction in solar systems. They are sun tracking, maximum power point (MPP) tracking or both [5]. These methods need intelligent controllers such as fuzzy logic controller or conventional controller such as PID controller. The advantage of the fuzzy logic control is that it does not strictly need any mathematical model of the plant. It is based on plant operator experience, and it is very easy to apply. Hence, many complex systems can be controlled without knowing the exact mathematical model of the plant [6]. In addition, fuzzy logic simplifies dealing with nonlinearities in systems [7]. The good of fuzzy logic control is that the linguistic system definition becomes the control algorithm. The FLC may implement on PIC and used to moves a motor attached to the solar panel to keep it toward the sun all the day.