This paper proposes into determining an appropriate electrical Vanadium Redox Flow Battery (VRB) model and its integration with a typical stand-alone wind energy system during wind speed variation as well as transient performance under variable load. The investigated system consists of a 3kW variable speed wind turbine with permanent magnet synchronous generator (PMSG), diode rectifier bridge, buck-boost converter, bidirectional charge controller, transformer, inverter, ac loads and VRB. Vanadium Redox batteries are well suited for this type of application because of their high efficiency, high scalability, fast response, long life and low maintenance requirements.Index Terms--VRB, battery modeling, wind energy, SOC, energy storage, stand-alone system.

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 two storage modules and a smart grid interface. The investigated system consists of three 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) and c) the medium/long term module (Vanadium Redox Flow Battery with power electronic converter). All of three 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.

IPv6 has yet to become more than a worthy successor of IPv4, which remains, for now, the dominant Internet Protocol. This is due to the complicated transition period through which the Internet will have to go, until IPv6 will completely replace IPv4. One of the challenges introduced by this transition is to decide which technology is more feasible for a particular network scenario. To that end, this article proposes the IPv6 Network Evaluation Testbed (IPv6NET), a research project whose ultimate goal is to obtain feasibility data in order to formulate a coherent, scenario-based IPv6 transition strategy. The paper presents the overview of IPv6NET, the testing methodology and empirical results for a specific network scenario. The presented empirical feasibility data includes network performance data such as latency, throughput, packet loss, and operational capability data, such as configuration, troubleshooting and applications capability.

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