Abstract : This paper deals with the design of a nonlinear state observer for parameters within the gas transfer part of a
fuel cell stack and its implementation on a small scaled embedded system. The fuel cell stack is of a proton exchange
membrane type, with parameters specific to vehicle applications. The observer is afterwards applied on a small scale
embedded board. In order to validate the embedded observer, a real time hardware in the loop testing is done using a cosimulation
between the embedded observer and the professional simulation software AMESim, linked with Simulink on a
windows platform. To act upon the nonlinear character of the system, a Takagi-Sugeno approach is implemented, where
the premise variables are unmeasurable. The procedure applies Lyapunov stability theory and by demanding bounded
stability instead of asymptotic one, the algorithm manages to eliminate the need for Lipschitz constants.
