An optimized MPPT circuit for thermoelectric energy harvester for low power applications

Abstract

A novel approach of maximum power point tracking (MPPT) control method for thermoelectric generator (TEG) is reported in this paper. The maximum power point tracking is achieved by using impedance matching principle. Unlike the existing MPPT methods, the proposed implementation does not require any voltage and current sensors and computations of any nature. The implementation of the MPPT control circuit is carried out using buck-boost DC/DC converter and a simple gating signal generator using only one Op-amp. The proposed method needs the least power consumption of the MPPT control circuit -less than 250 W. Experimental tests results obtained from series connected 3xTEGs (24 mm x 6 mm) show an average power harvesting of 5.6mW at T of 24 o C. The proposed thermoelectric energy harvester is used to power a battery which subsequently feeds a sensor node. The low power thermoelectric energy harvester system provides an overall power management circuit efficiency of up to 85%. The efficiency calculation takes care of power losses in the MPPT circuit. Index Terms-Low power thermoelectric energy harvesting circuit, High performance MPPT control, Constant impedance matching MPPT control circuit, Ultra-low power MPPT circuit for TEG.

Thermoelectric harvesters and the internet of things: technological and economic drivers

“…Maximum power point trackers and (super)capacitors or buffer rechargeable batteries are needed for TEG startup and to meet power surges occurring when SNs enter their active state (for communication and/or data processing). Although additional costs are nowadays small enough not to significantly change the economic comparison reported in section 6 [36][37][38], encompassing them in the design of SNs are believed to slow down consideration of TEGs as alternate power supplies.…”

Geothermal sources-based thermoelectric power generation: an attempt to enhance the rural electrification in southern Tunisia

“…In [8], Win et al introduced a MPPT strategy for TEGs, based on the impedance matching principle. The implementation of the proposed strategy has been achieved using a buck-boost DC/DC converter and a simple analog control driver.…”