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IEEE: The expertise to make smart grid a reality

Multiobjective Control of PEM Fuel Cell System With Improved Durability
A critical design goal of a fuel-cell-based renewable energy system in a smart grid scenario is to enable high efficiency while extending durability. This is particularly emphasized when the fuel-cell system becomes widely used. Towards this goal, the effort in this research paper is to develop multiobjective controllers to simultaneously realize both output tracking and durability improvement. More specifically, two types of controller are developed. With assumptions of knowledge of system parameters, the first controller enables exponentially stability of the closed-loop system. Then, with practical considerations of robustness, an adaptive extension of the first controller is developed, which is capable of handling possible mismatch between real parameters and parameters obtained from the manufacturer or system identification methods. The performance and stability is theoretically guaranteed by a Lyapunov-based proof. Together with theoretical analysis, several scenarios are considered and tested via Matlab/simulink-based simulation.
A 400nW single-inductor dual-input-tri-output DC-DC buck-boost converter with maximum power point tracking for indoor photovoltaic energy harvesting
Energy harvesting enables the remote sensors of the wireless sensor network to obtain power from the environment for their entire lifetime. For indoor remote sensors, amorphous silicon photovoltaic (PV) cell can be used to harvest energy from indoor lighting. Furthermore, if the power consumption of the sensor is low, e.g., the image sensor in [1], the power rating of the PV cell can be limited to tens or hundreds of microwatts to minimize the form factor of the sensor. However, as the output power of the PV cell varies greatly with illumination level [2] and the output voltage of the PV cell (VPV), an energy storage device, such as a battery, is required to regulate the harvester's output power. Furthermore, a DC-DC converter with a maximum power point tracker (MPPT) is needed to lock the PV cell at its maximum power point (MPP).
Enhanced broad-band extraordinary optical transmission through subwavelength perforated metallic films on strongly polarizable substrates
We demonstrate through simulations and experiments that a perforated metallic film, with subwavelength perforation dimensions and spacing, deposited on a substrate with a sufficiently large dielectric constant, can develop a broad-band frequency window where the transmittance of light into the substrate becomes essentially equal to that in the film absence. We show that the location of this broad-band extraordinary optical transmission window can be engineered in a wide frequency range (from IR to UV), by varying the geometry and the material of the perforated film as well as the dielectric constant of the substrate. This effect could be useful in the development of transparent conducting electrodes for various photonic and photovoltaic devices.
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