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Misfire monitoring is currently a mandatory On Board Diagnostic (OBD) regulatory requirement in most of the main automotive markets. The most common method used for misfire detection is the one based on the calculation of the derivative of the angular crankshaft velocity in which sharp variations of the derivative signal are associated to misfire events. Therefore, the misfire detection calibration is practically unique for a given engine hardware and installation. Within this context, this Paper will present a practical evaluation and also a computational simulation of the impact of an engine hardware change (front end accessory drive dumpers) on the calculated angular acceleration signal and, therefore, on the overall misfire detection capability. The outcomes of this study will ultimately define the need of calibration changes as well as support a future development of an analytical method to predicted impacts in misfire calibration.

In order to develop a control strategy for hydrogen fuel cell based powertrain, the dynamic models of the fuel cell stack and its auxiliary components must be devised. All The mathematical models currently available are able to estimate the polarization curve of the fuel cell at steady state condition, based on input variables like cathode and anode pressures and cell temperature. For automotive applications, the transient behavior of the fuel cell must be considered, since the powertrain is submitted to severe variations on the electrical power consumption during normal vehicle operation. Lumped models of the air and hydrogen supply systems, as well as other subcomponents like air compressor, coolers and humidifiers allow one to have a better understanding of the fuel cell behavior during transients and steady-state operation.