Bidirectional operation of the thermoelectric device for active temperature control of fuel cells

The thermoelectric (TE) device enables a conversion interface between the heat transfer and the electricity domain. Specifically, it can operate bi-directionally - Heat can be converted to electricity via the thermoelectric generator (TEG) effect and vice versa via the thermoelectric cooling (TEC) effect. In most state of the art research, the TE device is operated either in the TEG mode or TEC mode but very seldom in both modes for a single control objective. This paper proposes a thermal management system for a fuel cell who exploits the bi-directional characteristics of the TE device to achieve both temperature control and the possibility for energy harvesting when active control is not required. The studied scenarios involve a time-based simulation involving heat generation levels that are typical of a 500 W rated operating proton exchange membrane fuel cell (PEMFC). The overall dynamic system is simulated using Simscape library components in Simulink and the controller itself is implemented using MATLAB s-functions. An experiment involving electric heaters to emulate the fuel cell's body heat is also conducted to verify the proposed combined TEG-TEC control approach.