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and complexity of design that can be addressed with the electronics designer who has a solid technical background in power conversion and magnetic design. Inexpensive drivers can claim to meet the power factor requirements at full power, but as loading is dropped through dimming of the light emitted by the LED, these drivers will have a much lower power factor than 0.9. This will disqualify the fixture from meeting the Energy Star requirements. Adding metal oxide varistors (MOVs) is the simplest way to meet transient protection. Operating at -20°C temperature can be a challenge for the power designer and not all commercially available power supplies can comply. Careful selection of a driver can go a long way in obtaining Energy Star certification and avoiding costly delays in time to market as well as the assurance of offering quality LED lighting fixtures for this rapidly changing market. Illumination control The ability to control the illumination based on area occupancy is a growing field in the LED lighting market. Cost reductions can be realized by lighting only the path or the area that is being occupied in an office building or parking structure. Since LEDs are electronic devices, limiting the current can achieve the desired outcome in dimming the light and saving energy and costs. In some applications, both wired and wireless control systems are taking advantage of existing infrastructure developed for networking schemes. Moreover, LED drivers are built to have embedded IP addressing in order to interface with an electronic console to accept commands and change the light intensity based on occupancy sensing and other parameters. Fig. 2: SL Power’s LB240 AC/DC power supply features multi-cooling methods in a 3X5 package and meets EN55015 Class B. They can also report dynamic information, such as ambient temperature, back to the controlling console. This is an opportunity for the manufacturer of the LED drivers to influence lighting design in the early stages by providing flexibility in sensing and reporting critical information via wired or wireless antennas and receivers. With new technology offered, this can also be done via an AC line. The communication protocol is varied by application-specific LED fixtures. Area lighting uses Digital Addressable Lighting Interface (DALI) commands where entertainment lighting DMX-512 is widely employed. Remote Device Monitoring or RDM is the next step-up for wireless control in architectural lighting. No matter what the protocol is, an intelligent driver will be the future for powering LED light fixtures. France’s largest battery storage to stabilise power grid By Christoph Hammerschmidt The department Aube in the northeast of France plans to install the nation’s largest battery storage. The experiment is designed to underpin the development of renewable energies, in particular wind power, and try out new smart grid control schemes. While most people agree that renewable energies should be established, it is necessary to understand that renewables are not as continuously available as conventional energy sources – a factor that poses large challenges to the power grid. Energy storage technologies enable more flexibility for design and operation of the grid. Storing electric energy makes it possible to compensate for variations in energy production, control grid frequency and voltage – an important aspect in the quality of energy supply. The project Venteesa is designed to enable scientists and researchers to experiment and test new ways to stabilise the grid. The goal is finding the best practices, algorithms and tools for industrial implementation in the medium-voltage grid in terms of technology as well as in operational and business terms: The Venteesa scientists are developing methods to improve the overall grid efficiency and to integrate renewable energies into the grid. At the same time, the project will search for ways to optimise connecting costs. Towards this end, Veneesa employs Smart Grids. The energy storage developed by the French scientists is active at two levels: Firstly it enables the ideal energy flow throughout the grid, taking into account the technical conditions and factors such as voltage level frequency and more. Secondly it ensures that only the services are offered that suit best the needs of the grid and its users, taking into account forecasts about the energy production and the energy demand for one day ahead. Thanks to this multi-level service it will be possible to develop a new business model in which the cost for energy storage and technology roll-out can be distributed across the various actors. Thus, the project will create the base for tomorrow’s distribution network. Under geographical aspects the project is focusing on the Champagne – Ardenne region, France’s most important wind energy region. The demonstration installation is located in Vendeurvre-sur-Barse where an existing grid can be integrated into the trials. Here, two wind parks with 2 MW and 6 MW supply some 3.200 customers. The project, launched in 2011 by the French government agency for environmental protection and energy (ADEME), is designed to last 3 ½ years. The Venteea consortium includes eight enterprises (EFRE, Saft, Schneider Electric, General Electric, EDF R&D, Boralex, RTE and Made) as well as two universities (Troyes technical university and L2EP). www.electronics-eetimes.com Electronic Engineering Times Europe July-August 2015 37


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