All-condition economy evaluation method for fuel cell systems: System efficiency contour map

Abstract For fuel cell research, fuel economy evaluation methods for fuel cell systems are the basic tools; however, current fuel economy evaluation methods do not meet the demand for comprehensive analyses of the economy of fuel cell systems. In this study, we propose an all-condition economy evaluation method for fuel cell systems. To estimate the all-condition state of fuel cell systems, we developed a 1-D water transport model and an air compressor model for all operating conditions. Inspired by the knowledge of internal combustion engines, we developed an innovative fuel cell system efficiency contour map for evaluating all operating conditions. This method decouples the economy evaluation from test operating conditions and control strategy and demonstrates the fundamental characteristics of fuel cell systems. Based on the fuel cell system efficiency contour map, we propose an optimized control strategy for fuel cell hybrid vehicles, which reduces fuel consumption by 1.45%–13.14%.