Photovoltaic Array Modelling with P&O MPPT Algorithm in MATLAB F.Z. Hamidon Electrical Technology Section UniKL – British Malaysian Institute Gombak, Selangor, Malaysia fatimahzaharah@bmi.unikl.edu.my P.D. Abd. Aziz Electrical Technology Section UniKL – British Malaysian Institute Gombak, Selangor, Malaysia pusparini@bmi.unikl.edu.my N.H. Mohd Yunus Communication Technology Section UniKL – British Malaysian Institute Gombak, Selangor, Malaysia noorhidayahm@bmi.unikl.edu.my Abstract—Photovoltaic (PV) arrays are used in many terrestrial applications. It exhibits a non-linear i-v characteristic which electrical energy production is depending on typical conditions such as solar irradiance and temperature. For best utilizations, the PV arrays must be operated at their maximum power point (MPP) via good implementation of Maximum Power Point Tracking (MPPT) algorithm technique. It is important to be aware that the MPP varies with respect to the characteristic of PV arrays in various conditions as mentioned above. Thereby, a detailed simulation model of PV array by employing the most popular MPPT algorithm of Perturb & Observe (P&O) has been developed in MATLAB. This model allows characterizing the PV array in terms of different temperature and irradiance as variable parameters. The parameters’ variations under Malaysian conditions are also being considered. The outputs of the model are i-v and p-v characteristics as well as the voltage, current and power at MPP of the PV array are simulated from MATLAB script file. The simulation results will be presented and analyzed in this paper. Keywords- PV Arrays; i-v and p-v Characteristics; P&O MPPT I. INTRODUCTION Prior to the development of PV system, there are many PV arrays with different specifications available in the market. The PV arrays must be operated at its highest energy conversion output by continuously utilizing the maximum available power of the array. The electrical system powered by PV arrays requires special design considerations due to varying nature of the solar irradiation level as well as the operating temperature [1]. The output of a PV array is highly non-linear and to simplify the array to a constant voltage source is often not appropriate. Several models for PV arrays have been proposed in the literature [1]-[4]. The level of details inherent in these models is helpful to have a flexible model that can be used on measured PV array characteristics. Tracking the MPP of a PV arrays is usually an essential part of a PV system. As such, many MPPT methods have been developed and implemented [5]. The problem considered by MPPT techniques are to automatically find the voltage VMPP and current IMPP at which a PV array should operate to obtain the maximum power output PMPP under a given temperature and irradiance. Among all available techniques, a simple and effective MPPT of P&O algorithm were embedded on MATLAB script file to attain the maximum power of PV array in different solar irradiance and temperature condition parameters. The simulation work also will observe on the MPP of PV array conditions with respect to the specified weather in Malaysia. The Malaysia’s typical daily irradiance profile was obtained from a study on the availability of daylight from tropical skies i.e. as reported in [6]. In the PV array model evaluation, a temperature of 27 o C is chosen as the typical Malaysian morning and evening temperature while 33 o C is chosen as the temperature at noon. This paper defines a circuit-based mathematical simulation model for a PV array in order to allow estimate the electrical behavior of the array with respond to the changes on environmental parameter of solar irradiance and temperature. A particular typical numbers of MSX-10Lite PV modules wired together into array both in series and parallel connection was used for the PV array model evaluation. This PV module consists of a total of 36 PV cells in series and a single PV cell in parallel strings. On the other hand, the PV array is composed of 6 parallel modules and 8 series modules. The simulation model of the PV array is based on the standard single-diode representation of the PV cell equations. The model parameters for the purpose of simulation in MATLAB were obtained from manufacturer datasheet of the PV module. The modeling of PV array and P&O MPPT algorithm implementation on MATLAB script file will be further discussed in Section II and Section III respectively. Section IV investigates the results from the simulation work. Finally the conclusion is drawn in Section V. II. PV ARRAY MODELLING The PV array characteristics significantly influence the design of the inverter and the controller for the whole PV system. Therefore, it is essential to review the model of the PV array as the preliminary design to obtain the respective i-v and p-v characteristic curves. A circuit-based mathematical simulation model for a PV array was designed according to the equivalent circuit diagram of a silicon PV cell in single-diode representation that illustrated in Figure 1. The PV input is represented with a dc current source. It has one diode connected in parallel, one resistor connected in series and another resistor connected in parallel. Then, it is connected to a Fatimah Zaharah Hamidon currently is a lecturer from Universiti Kuala Lumpur – British Malaysian Institute who specialized in power electronic field of study in renewable energy application. She can be contacted by email via fatimahzaharah@bmi.unikl.edu.my.