Contribution to the optimization of the autonomous photovoltaic solar systems with hybrid storage for loads with peak power with constraints of volume and loss of power supply probability

Abstract

The storage o???? energy is a ????undamental aspect in the per????ormance and the li????espan o???? the autonomous photovoltaic solar systems. The batteries with lead-acid are the most widespread technology o???? storage, because o???? their great availability, their low cost and their weak maintenance. They are generally ????ailing because o???? certain de????ects such as: the strati????cation, sulphating, short-circuits, oxidation…These various de????ects strongly a????ect the li????espan o???? the batteries and thus the li????etime cost o???? the solar system. The appearance o???? these de????ects is ????or most o???? the time related to a non-optimal dimensioning o???? the system which does not take into account the starting peak power o???? certain electrical appliance. Indeed, the taking into account o???? these peak powers generate an oversizing o???? the batteries, consequently o???? the photovoltaic ????eld and thus a very signi????cant investment. To answer these problems, we proposed in this work a method o???? optimization o???? the autonomous solar systems by integrating ultracapacitors to meet the requirement in peak power. A program o???? optimization was developed in Matlab ????or this purpose, simulations were also done under Simulink to explore the advantages o???? the integration o???? ultracapacitors in the element o???? storage o???? an autonomous PV system with various pro????les o???? load. The program o???? optimization has a step o???? time able to collect the ????uctuations o???? the load and pro????les o???? solar radiation and generates the best orientation according to the site so that the photovoltaic panel generates the maximum annual power. The program also makes it possible to determine the ????nancial economy carried out by exploiting the Hybrid System o???? Storage with ultracapacitors and proposes various combinations o???? panels, batteries and ultracapacitors compared to LVD limit ????xed with the li????etime cost and the LPSP corresponding. The management system o???? energy ????or the complete system was studied with imposed constraint the ????ull charge o???? ultracapacitors between the peak powers.