University: University of Michigan
Team Members: Sam DeBruin, Branden Ghena, Prabal Dutta,
TI Parts Used:
PowerBlade is the smallest, lowest cost, and lowest power AC plug-load meter that measures real, reactive and apparent power, and reports this data, along with cumulative energy consumption, over an industry-standard Bluetooth Low Energy radio. Achieving this design point requires revisiting every aspect of conventional power meters: a new method of acquiring voltage; a non-invasive, planar method of current measurement; an efficient and accurate method of computing power from the voltage and current channels; a radio interface that leverages nearby smart phones to display data and report it to the cloud; and a retro power supply reimagined with vastly lower current draw, allowing extreme miniaturization. PowerBlade occupies a mere 1.1 in x 1.1 in footprint, offers a 1/16 in profile, draws less than 6 mW itself, offers 4.3% error on unity power factor loads in the 50-350 W range and slightly worse for non-linear and reactive loads, and costs $11 in modest quantities. This new design point enables affordable large-scale studies of plugload energy usage – an area of growing national importance.
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