Energy harvesting
Transcription
Energy harvesting
Human powered IoT Mario Dellea mardi 24 Novembre 2015 [email protected] 1 Energy harvesting is the process by which energy is captured, stored and managed https://cnes.fr/fr Rosetta & Philae on Tchouri Philae’s activity depends of the energy available 2 Wearable and implantable systems Form factor : Wearable : 2D (flat & flexible) Implantable : 3D -> 1cm2 -> 1mm3 The harvested power is proportional to the size 3 Autonomy with thin-film batteries Average power demand 10mW 1mW 40x30mm 10mAh 1.5V (1250mWh/cm2) Autonomy for 1cm2 battery Energy harvesting will improve autonomy 5 days 4 50 days Main sources available on the human body • Harvestable average ambient power : about 1 mW cm 2 • Difficult to predict, except for heartbeat and breath • Useful for microwatts average power applications 5 Vullers_VanSchaijk_IMEC_2009_Micropower_Energy_Harvesting Human energy harvesting in the past 1770 Abraham-Louis Perrelet (self-winding watch) 1972 Synchronar (solar watch) 1980 Thermatron Bulova (thermoelectric watch) 1997 Autoquartz (self-winding electronic watch) 6 Power Demand versus Power Harvested Power Power Harvested Average Power Harvested Power Demand Time Average Power Demand A storage element is needed! 7 Nanopower Energy & Power Management Nanopower Energy Harvester MPPT Primary battery VS Nanopower Energy Manager Storage device choice is not that Nanopower Energy Storage SM / CDC DVS / AVS AC simple! Nanopower Wearable Application 8 Energy storage devices Lower charge/discharge Longer charging time Ragone chart Hybrids Storage device choice depend of the application! Higher charge/discharge 9 Shorter charging time Example 1 : RFID powered flow sensor Implantable transducer for monitoring the flow of cerebrospinal fluid for the treatment of hydrocephalus NFC antenna • • • • • RFID powered flow sensor ultra-thin package pressure sensor (valve) 10 (battery) Example 2 : Intraocular pressure sensor to aid glaucoma patients Powered by harvesting light that enters the eye through the cornea 1.5mm 3 ISSCC 2011 A Cubic-Millimeter Energy-Autonomous Wireless Intraocular Pressure Monitor D. Blaauw, D. Sylvester, A. Arbor; University of Michigan 11 Example 3: Piezoelectric energy harvester Harvesting mechanical energy, often needs a quite complex mechanical system 12 Micro Blood Pressure Energy Harvester for Intracardiac Pacemaker; Deterre, Lefeuvre, 2014 Energy Management Controller 13 Smart Power Management Ultra low quiescent regulator Wake-up function MPPT Maximum Power Point Tacking USB Charger Ultra low input voltage and power Coldstart : 0.3V / 3 μW Operating 0.1V / 1 μW Ultra low power solution 15 nA on battery in protection mode 125 nA supplying low-power apps Fast cold-start Aimed to feed the application before recharging the battery Primary Cell Life Time Extension Flexible interface SPI or I2C interfaces Only few passive components Configuration by E2PROM Power control Luxmeter 14 EM8500 : the only usable for wearable applications 15 Thank you for your attention ! [email protected] 16