Autonomous Multisensor System Powered by a Solar Thermoelectric Energy Harvester With Ultralow-Power Management Circuit

Author(s)

Dias, Pedro Carvalhaes ^[1] ; Oliveira Morais, Flavio Jose ^[1] ; de Morais Franca, Maria Bernadete ^[2] ; Ferreira, Elnatan Chagas ^[1] ; Cabot, Andreu ^{[3, 4]} ; Siqueira Dias, Jose A. ^[1]

Affiliation

^[1] Univ Estadual Campinas, Sch Elect & Comp Engn, Dept Elect & Microelect, BR-13083820 Campinas, SP - Brazil

^[2] Univ Estadual Londrina, BR-86057970 Londrina - Brazil

^[3] Catalonia Inst Energy Res, Barcelona 08930 - Spain

^[4] Inst Catalana Recerca & Estudis Avancats, Barcelona 08930 - Spain

• Document type: Journal article
• Source: IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT; v. 64, n. 11, p. 2918-2925, NOV 2015.
• Web of Science Citations: 24

Abstract

An autonomous multisensor system powered by an energy harvester fabricated with a flat-panel solar thermoelectric generator with an ultralow-power management circuit is presented. The multisensor system was tested in an agricultural application, where every 15 min the values of the temperature, air humidity, and solar radiation have to be measured and stored in a mass memory device (a Secure Digital card), with their respective time stamp. The energy-harvesting switching dc-dc converter is based on a low-input-voltage commercial integrated circuit (LTC3108), which charges a 1.65-F supercapacitor up to 5.0 V. A novel ultralow-power management circuit was developed to replace the internal power management circuitry of the LTC3108, and using this circuit, the operation of the system when no energy can be harvested from the environment is extended from 136 h to more than 266 h. The solar thermoelectric generator used for the energy harvesting is composed of a bismuth telluride thermoelectric generator with a 110-mV/degrees C Seebeck coefficient sandwiched between a 40 cm x 40 cm anodized aluminum flat panel and an aluminum heatsink. On a sunny winter day in the southern hemisphere (12 August 2014, at Campinas, SP-Brazil, Latitude: 22 degrees 54'), the energy supplied by the harvesting system to the supercapacitor was 7 J. (AU)

• FAPESP's process: 12/20862-4 - A low-power, low voltage autonomous single probe heat pulse soil moisture sensor based on semiconductors with energy harvesting using thermoelectric generators
• Grantee: Pedro Carvalhaes Dias
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 14/01470-3 - Design and fabrication of an autonomous heat pulse probe soil water moisture sensor using semiconductor devices fabricated with sprayed semiconductor ink on alumina, integrated with a bite thermoelectric generator
• Grantee: Pedro Carvalhaes Dias
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate