Design and Experimental Investigations of an Energy Storage System in Microgrids

The continuous increasing in distributed renewable generation mainly based on wind and solar has complicated recently the normal grid operations. An accurate development in proper energy storage systems with high ability to store and supply energy on demand should effectively eliminate the potentially adverse negative impacts of actual grid operation technologies, such as severe power fluctuation provided by intermittent power generations and photovoltaic arrays. Therefore, the hydrogen economy is regarded as continuous research that can be understood as a significant effort to modify the actual energy system into a system that combines the hydrogen advantage of as energy carrier with high efficiency of proton exchange fuel cells (PEMFC) as electrochemical processes that converts energy power into electricity and heat. In this chapter an experimental investigation on the performance of an integrated microgrid, installed at the National Centre for Hydrogen and Fuel Cell, is presented. This system is equipped with specific components such as photovoltaic generator, solid polymer electrolyzer producing 1 m3 h−1, 4.2 kW PEMFC and power conditioning system to develop different topologies. Experimental investigations of an energy storage system in microgrids were analysed under realistic scenarios in different environmental conditions. The water electrolyzer stack is powered mainly by the solar PV energy source, then the produced hydrogen is stored in the hydrogen tank. The role of water electrolyzer is to generate hydrogen when the generated power by solar PV is greater than the power demand, and the role of PEMFC is to consume the generated hydrogen from water electrolyzer and to transform in electrical power energy. The target of the present work has been to assess the dynamic model of both systems to investigate the effect of these elements into the microgrid using measurements of the real systems. Modelling of the described system has been achieved using the MATLAB/Simulink. The model parameters have been acquired from manufacturer’s performance data-sheets. Based on above information, the proposed concept combining the PEMFC and water electrolyzer hybrid sources could offer an important improvement for real time power imbalances. Therefore, this chapter take into account the control system based power conditioning and energy management of a controllable electrolyzer in order to investigate the real time fluctuations of microgrid’s real power balance.