Smart electrical energy storage system for small power wind turbines

Energy storage devices and solutions are required for power quality and balance within wind systems. In the context of rapidly expanding of distributed energy sources, the wind energy converters are in the center of interest. In this case, the direct dependence of the power generation capability for a given wind speed represents a major problem of wind energy conversion with regard to large-scale network integration. This paper proposes an overall solution which consists of a wind plant with a Smart Storage Modular System (SSMS) where the wind source -as stochastic one- is coupled over a dc bus with three storage modules and a smart grid interface. The investigated system consists of fours modules: a) the stochastic module (variable wind turbine with PMSG and ac/dc + bust converters), b) the short term storage module (flywheel with power electronic converter), c) the medium/long term module (Vanadium Redox Flow Battery with power electronic converter) and d) the medium term module (Lead Acid Battery). All of modules are interfaced with the network and insulated loads by a grid interface module (power electronic converter, filter and transformer). To the related SSMS, are accomplished computer simulations. In order to validate them, laboratory tests are also presented.