Proton exchange membrane fuel cell system diagnosis based on the signed directed graph method

The fuel-cell powered bus is becoming the favored choice for electric vehicles because of its extended driving range, zero emissions, and high energy conversion efficiency when compared with battery-operated electric vehicles. In China, a demonstration program for the fuel cell bus fleet operated at the Beijing Olympics in 2008 and the Shanghai Expo in 2010. It is necessary to develop comprehensive proton exchange membrane fuel cell (PEMFC) diagnostic tools to increase the reliability of these systems. It is especially critical for fuel-cell city buses serving large numbers of passengers using public transportation. This paper presents a diagnostic analysis and implementation study based on the signed directed graph (SDG) method for the fuel-cell system. This diagnostic system was successfully implemented in the fuel-cell bus fleet at the Shanghai Expo in 2010.

► Combination of qualitative and quantitative modeling for fuel cell system diagnosis.
► Establishment of the SDG diagnosis model for PEM fuel cell system.
► The fuel cell system failure and components degradation can be well detected and observed at the Shanghai Expo demonstration in 2010.