Research on Control Strategy of Proton Exchange Membrane Fuel Cell Waste Heat Recovery System

Proton exchange membrane fuel cells (PEMFCs) are widely employed in transportation, portable power systems, and stationary power generation due to their high efficiency, low operating temperature, and rapid start-up capability. However, a substantial amount of waste heat is generated during their operation. To ensure stable and reliable performance, this excess heat must be effectively dissipated to maintain a consistent stack temperature. To enhance overall energy utilization, a waste heat recovery system is implemented, which captures residual thermal energy while the cell generates electricity. This is achieved by transferring heat to tap water stored in a thermally insulated water tank, thereby significantly improving system efficiency. In this study, a control strategy for waste heat recovery is proposed. A proportional-integral-derivative (PID) controller is employed to regulate either the opening of a proportional control valve or the speed of the tap water pump. By intelligently switching between heat dissipation and overflow modes, the proposed strategy enables efficient utilization of residual heat while ensuring the stability of the fuel cell stack temperature. The effectiveness of the proposed control strategy is validated through experiments conducted on a dedicated simulation platform.