Battery-less non-contact temperature measurement system powered by energy harvesting from intentional human action

Abstract

This paper presents a battery-less non-contact temperature measurement system powered by energy harvesting from intentional human action. The conversion between the human action and electrical energy is provided by a hand-crank electromagnetic (EM) converter. The AC voltage generated by the EM converter has time-varying amplitude and frequency and is rectified by a metal–oxide-semiconductor field-effect transistor-based voltage doubler active rectifier circuit. The harvested energy is efficiently stored into multiple capacitors by the innovative sequential charging of storage capacitors technique, and used to power a micro electro mechanical system thermopile sensor with related signal conditioning electronics plus a liquid-crystal display to visualise the temperature readings. With a force of about 29.4 N over 2 cm applied to the EM converter, the power management circuit is able to extract an energy of 27.5 mJ and power the non-contact temperature measurement system for about 33 s.