Development of an energy harvesting system based on a thermoelectric generator for use in online predictive maintenance systems of industrial electric motors

In the era of the Fourth Industrial Revolution, improvements in maintenance routines for industrial electric motors are continuously being made, allowing for the development of Predictive Maintenance (PdM) Online. PdM can be executed by employing small embedded systems that are affixed to electrical machines. Although a small-capacity battery can effectively power an ultra-low consumption sensor, the extensive use of batteries can contribute to increased environmental pollution. An effective approach to obviate the necessity for batteries is to employ energy-harvesting techniques from electric motors. In this regard, this paper aims to contribute to advancements in research concerning the harvesting of thermoelectric energy from industrial electric motors to create a self-sustaining Internet of Things (IoT) device. To achieve energy autonomy, the construction of a mechanical coupling for the attachment of Thermoelectric Generators (TEGs) was proposed, along with the maximization of small TEG production and the optimization of the electronic circuit for energy management. The mechanical prototype for affixing TEGs to low-power electric motors enabled a maximization of the generated energy by the TEGs, and the electronic circuit optimization process resulted in the generation of 370.10 μW, exceeding the energy requirements for making the IoT device self-sustaining by 54.21%.