Fault-tolerant control for PEMFC and its DC/DC converter

Abstract

Over the last decade, fault-tolerance has gained a growing interest from the scientific community, particularly for Proton Exchange Membrane Fuel Cell (PEMFC) and its DC/DC converter. Fault-tolerance has two main objectives: provide high-level improvement in system availability and lead to substantial reduction in maintenance costs. Generally, fault-tolerance refers to a Fault-Tolerant System (FTS) and/or Control (FTC). PEMFC and its DC/DC converter must respond to challenging issues for stationary and automotive applications, in terms of reliability. Indeed, the unavailability of the current Fuel Cell System (FCS) stops to market these components on a large scale. In PEMFCs, the Membrane Electrode Assembly (MEA) can be subjected to different failures: membrane break, internal gas leakage, cell flooding or drying, poisoning of the catalyst areas… By comparison, in DC/DC converters, power switches ranked the most delicate components. Once the failure has been detected, FCS stop must be avoided. In order to ensure the availability of the FCS and/or to minimize the undesirable effects of degraded operating mode on FCS, FTS and FTC must be used. This paper presents a FTC applied to the DC/DC converter in case of drying membrane failure in PEMFC. The FTC consists in degrading the converter performances through its control in order to bring back the PEMFC in an optimum operating condition. The developed FTC is implemented experimentally on a MicroAutoBox. The obtained experimental results demonstrate the efficiency of the FTC to improve the performances of the PEMFC.