Simulation of thermoelectric generator system by periodically alternating thermal energy harvesting
Abstract: As a environmentally friendly thermal energy harvesting device, thermoelectric generator (TEG) can convert heat into electricity directly. Therefore, researchers have made great efforts to detailed explanation the principium including established many steady-state models to describe the TEG system converting heat into electrical energy. However, in fact variable temperature heat source is a more common situation, the temperature difference occurred by TEG changes over time in nearly all situations. The steady-state simulation model simplifies the complexity on the one hand but also deviates from the facts on the other hand. In this paper, we built a transient simulation model that includes time variables under the condition of a periodically changing temperature heat source that it accurately illustrates the change of TEG's output power characteristics over time. A periodic heat source is obtained by changing the current of a Joule heater. The simulation model uses comsol's solid heat transfer and electromagnetic modules. The simulation result is containing time variables and shows that a periodic heat source, instead of a constant heat source, can improve the conversion efficiency of a thermoelectric generator.