Control of an afterburner in a diesel fuel cell power unit under variable load

• Published in: Journal of power sources 2017-01, Vol.338, p.117-128
• Main Authors: Dolanc, Gregor, Pregelj, Boštjan, Petrovčič, Janko, Samsun, Remzi Can
• Format: Article
• Language: English
• Subjects: Afterburner; Autothermal diesel reforming; Auxiliary power unit; Fuel cells; Process control
• ISSN: 0378-7753; 1873-2755
• DOI: 10.1016/j.jpowsour.2016.10.082

In this paper, the control system for a catalytic afterburner in a diesel fuel cell auxiliary power unit is presented. The catalytic afterburner is used to burn the non-utilised hydrogen and other possible combustible components of the fuel cell anode off-gas. To increase the energy efficiency of the auxiliary power unit, the thermal energy released in the catalytic afterburner is utilised to generate the steam for the fuel processor. For optimal operation of the power unit in all modes of operation including load change, stable steam generation is required and overall energy balance must be kept within design range. To achieve this, the reaction temperature of the catalytic afterburner must be stable in all modes of operation. Therefore, we propose the afterburner temperature control based on mass and thermal balances. Finally, we demonstrate the control system using the existing prototype of the diesel fuel cell auxiliary power unit. •A control system for an afterburner of a diesel fuel cell power unit was developed.•It is a part of complete control system of a fuel cell auxiliary power unit.•The goal is stable temperature and steam generation in all operating modes.•A feedforward and feedback control was used for disturbance rejection.•The control system was tested on the auxiliary power unit prototype.