A MODEL OF AUTONOMOUS PHOTOVOLTAIC SYSTEM WITH A PULSE-WIDTH BATTERY CHARGE CONTROLLER

Abstract

In this paper the model of autonomous photovoltaic system with a pulse-width battery charge controller is proposed. The Matlab/Simulink environment was used to build the model. The main blocks, structure and features of the model are described, and its capabilities are demonstrated. The behavior of the autonomous photovoltaic system was simulated under variation of the main external factors, such as the solar energy flux and the temperature of the photovoltaic module. The processes taking place in the system under influence of changes in these factors were analyzed, and their effect on the parameters of the main components of the system was clarified. It is shown that when the temperature of the module increases and the solar flux decreases, the voltage of the module approaches the voltage of the battery, which results to increment in efficiency of the pulse-width charge controller. This outcome correlates with the results described in some literature sources. The possibility of using the developed model to study of the real autonomous photovoltaic systems in specified climatic conditions is demonstrated. The operation of the “Tourist-80 Compact” portable autonomous photovoltaic station during a typical day of July in the climatic conditions of the Kherson region was simulated. Based on the analysis of the energy data obtained from the simulation, it was shown that under the condition of allowed battery discharge up to 50% this autonomous station is able to ensure the electric energy consumption of 545 W h of 545 W h per day, but in the case of full recovery of the battery charge during a light day it is needed to reduce the consumption to 305 W h, which is sufficient for 3 mobile phone charging cycles, one hour of a portable LED lamp operation, and exploitation of a portable car refrigerator during 5.5 hours.