Active Thermal Management for an Automotive Water-Cooled Proton Exchange Membrane Fuel Cell by Using Feedback Control

Proton exchange membrane fuel cell (PEMFC) appears as a green energy to solve the environmental and energy problems in the automotive industry. Temperature changes in PEMFC affect fuel cell's efficiency and lifetime. If the stack temperature is too low, the electrochemical reaction rate slows down, leading to inefficiency and shortening the working life of the stack. However, too high stack temperature may dry the membrane and decrease proton conductivity, or even destroy the membrane. Therefore, to avoid stack temperature fluctuations and maintain proper stack temperature, a thermal management-oriented model of the vehicular water-cooled PEMFC is presented, which is based on electrochemical reactions and thermodynamics. A PI associated with an ON/OFF feedback controller is designed to control the output mass flow rates of the circulating water pump and the radiator fans. To test the efficacy of the proposed model and controller, different load currents including typical driving cycles are applied. The results indicate that the stack temperature well tracks the reference temperature, and the temperature difference of cooling water in and out of the stack is less than 6°C.