Mehdi Dali Jamel Belhadj Xavier Roboam Regular paper Design of a stand-alone hybrid Photovoltaic-Wind generating system with battery storage - Energy based modeling with losses integration - Energy management control strategy In this paper the authors have developed an isolated network for very low voltage (VLV) decentralized energy production and storage based on renewable energy (hybrid system: photovoltaic and wind). An energy based model of stand-alone hybrid photovoltaic-wind generating system is presented, using bond graph approach. An equivalent average modeling of a hybrid photovoltaic-wind generating system is used. The modeling of the components of the global system is developed with the integration of converters losses involved in the solar and wind generating subsystems. It is shown that this model is interesting for analyzing the dynamic behavior of the system and for designing the control strategy. The energy management and control of the photovoltaic and wind subsystems are based on voltage and current control with Maximum Power Point Tracking (MPPT) allowing the optimal transfer of power to DC load. Keywords: Hybrid system; photovoltaic energy; wind energy; battery storage; system modeling; converter losses; Bond graph; Control strategies. 1. INTRODUCTION The rising rate of consumption and the price of fossil fuels and the environmental problems caused by the conventional power generation draw worldwide attention to renewable energy technologies. In fact, renewable energy systems are pollution free, takes low cost and less gestation period, user and social friendly. However, renewable power unit based on single source (wind or solar source) may not be effective in terms of cost, efficiency and reliability. A viable alternative solution is by combining these different renewable energy sources to form a hybrid energy system [1, 2]. Hybrid energy system is an excellent solution for electrification of remote rural areas where the grid extension is difficult and not economical. Such system incorporates a combination of several renewable energy sources such as solar photovoltaic, wind energy and may be conventional generators for backup. A system using a combination of these different sources has the advantage of balance and stability that offers the strengths of each type of sources that complement one another. The main objective is to provide 24 hours demand quality power in remote communities. Hybrid systems can provide electricity at a comparatively economic price in many remote areas. In order to obtain electricity from a hybrid system reliably and at an economical price, its design must be optimal in terms of operation, control and component selection. Many topologies are available for hybrid systems, depending on interface converters between the sources and the interconnection DC bus (Low DC voltage “LV”, Very Low DC voltage “VLV” loads). We have investigated to design an optimum architecture of hybrid system with Very Low Voltage (VLV) DC (48V). With this DC bus, this stand-alone hybrid system can be implemented into rural or urban areas [3], [4]. Such systems are used today in many applications as battery charging, water pumping and desalination [5-7]. This paper aims at the averaged modeling and energy flow analysis of a stand-alone hybrid generating system comprising of wind and photovoltaic subsystems. The average model is used because it’s adequate for long time dynamic simulations. Both, photovoltaic JES Proof