Control-Oriented Modeling of the Cooling Process of a PEMFC-Based μ-CHP System

Micro-combined heat and power systems (mu-CHP) based on proton exchange membrane fuel cell stacks (PEMFC) are capable of supplying electricity and heat for the residential housing sector with a high energy efficiency and a low level of CO2 emissions. For this reason, they are regarded as a promising technology for coping with the current environmental challenges. In these systems, the temperature control of the stack is crucial, since it has a direct impact on its durability and electrical efficiency. In order to design a good temperature control, however, a dynamic model of the mu-CHP cooling system is required. In this paper, we present a model of the cooling system of a PEMFC-based mu-CHP system, which is oriented to the design of the temperature control of the stack. The model has been developed from a mu-CHP system located in the laboratory of our research team, the predictive control and heuristic optimization group (CPOH). It is based on first principles, dynamic, non-linear, and has been validated against the experimental data. The model is implemented in Matlab/Simulink and the adjustment of its parameters was carried out using evolutionary optimization techniques. The methodology followed to obtain it is also described in detail. Both the model and the test data used for its adjustment and validation are accessible to anyone who wants to consult them. The results show that the model is able to faithfully represent the dynamics of the mu-CHP cooling system, so it is appropriate for the design of the stack temperature control.