Journal of Energy Technologies and Policy www.iiste.org ISSN 2224-3232 (Paper) ISSN 2225-0573 (Online) Vol.1, No.2, 2011 18 Fuzzy Intelligent Controller for the Maximum Power Point Tracking of a Photovoltaic Module at Varying Atmospheric Conditions Aurobinda Panda * ,M.K.Pathak, S.P.Srivastava Department Of Electrical Engineering, IIT Roorkee, PO box 247667, Roorkee, India * E-mail of the corresponding author: aurobind.panda@gmail.com Abstract This paper presents the modeling of a photovoltaic (PV) module at varying atmospheric conditions such as irradiation and temperature. It also includes the maximum power point tracking (MPPT) of the PV module using conventional perturb and observe (P&O) method and fuzzy logic controller. For the performance analysis, the simulation of the PV module along with MPPT controller is done by using MATLAB/Simulink software. The voltage, current and power transitions at varying irradiation and temperature conditions is observed using conventional P&O and fuzzy logic based MPPT controllers. Finally the percentage improvement in power tracking time by fuzzy logic controller against the P&O controller has been evaluated Keywords: Photovoltaic Module, MPPT, P&O method, Fuzzy logic Controller, Irradiation 1. Introduction The recent change in the environmental conditions such as global warming and the rapid increase in the demand for electricity led to a need for a new source of energy that is cheaper and sustainable with less carbon emissions. Solar energy has offered promising results in the quest of finding the solution to the problem.If used in a proper way then it has the capacity to fulfil numerous energy needs of the world. That is why researchers are more inclined towards this area. A photovoltaic system converts sunlight into electricity by photovoltaic effect.Photovoltaic (PV) electrical energy generation provides several advantages with respect to other energy sources like it uses the inexhaustible world-wide available sunlight as a source of energy, it does not generate environmental pollutants and also the PV panels used requires minimum maintenance. However, the major challenges in such type of system includes the high cost of PV panel and also the solar energy is a dilute source of energy and its availability varies widely with time and with different atmospheric condition. So, it is very necessary to make a complete utilization of solar energy in such available conditions and for this maximum power point tracking controller is essential for the PV system to extract maximum power at given atmospheric condition. A MPPT is used for extracting the maximum power from the solar PV module and transferring that power to the load [1, 4]. A dc/dc converter (step up/ step down) serves the purpose of transferring maximum power from the solar PV module to the load. A dc/dc converter acts as an interface between the load and the PV module as shown in Figure 2. By changing the duty cycle the load impedance as seen by the source is varied and matched at the point of the peak power with the source so as to transfer the maximum power[5].Therefore MPPT techniques are needed to maintain the PV array’s operating at its MPP [6]. Many MPPT techniques have been proposed in the literature such as Perturb and Observe (P&O) methods [4, 6-9], Incremental Conductance (IC) methods [1, 4, and 10], etc. The main aim of this paper is to present the mathematical modelling and simulation of PV module and also to assemble an efficient MPPT controller with the PV module to extract maximum power from it. Here basically conventional MPPT algorithm is compared with a fuzzy intelligent controller based on simulation results.