Modeling and Design of Thin-Film π-Type Micro Thermoelectric Generator Using Vacuum/Insulator-Hybrid Isolation for Self-Powered Wearable Devices

Abstract

Modeling and design of a thin-film $\pi $ -type micro thermoelectric generator ( $\mu $ TEG) using a new module structure, which is powered by body heat, are demonstrated for wearable device (WD) applications. The module has a vacuum/insulator-hybrid isolation structure enabling it to achieve high output power, whose interspace between the cold-side and convex-shape hot-side plates is isolated by an insulator for the thermopile integration region and by vacuum for its outside region. A lumped-constant circuit model and structure optimization algorithm for the $\mu $ TEG module using a single tradeoff parameter for the thermal and electrical resistances are developed so as to maximize the output power, based on a homeothermic system model of humans with the thermogenic action limit of humans. The developed model can accurately reproduce results analyzed by a distributed-constant circuit model. The optimum design of this $\mu $ TEG module can exhibit sufficiently high output power applicable to a power source of self-powered WDs.