A Wearable Solar Energy Harvesting Based Jacket With Maximum Power Point Tracking for Vital Health Monitoring Systems

Abstract

Wearable sensors and electronic devices have gained a lot of attention during the last few years. The advances in low power wearable gadgets have the research venue in the field of energy harvesting to exclude or supplement the battery’s power. Solar energy harvesting is a suitable source to power wearable gadgets. This work presents a novel wearable solar energy harvesting based jacket that can power the in-situ vital health monitoring system (VHMS). The developed VHMS comprised of sensors to measure several data and transferred through various Modules every 3 min with an emergency alert option. To integrate the Solar Energy harvester (SEH) and VHMS, a novel maximum power point tracking is designed, fabricated and tested to compensate the battery during diffused light as power is recorded to be as low as 7.95 × 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-5</sup> mW at an optimal load of 10 kΩ. Ten flexible solar cells (each 146 mm × 167.5 mm in size) placed each inside a transparent pouch stitched to a jacket. An individual and series configuration of all solar cells is tested in-lab and outside in real environment under different illuminance and irradiance. At an optimal load resistance of 1.5 kΩ, the developed self-powered, smart jacket is capable to generate a voltage of 45 V and power of 1282.57 mW, under lights’ illuminance of 41000 lux and irradiance of 780 W/m <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> . The proposed SEH has been validated through a prototype system. Its performance compares favorably against various brands based on size, power, modes to communicate and sensors.