A Development of the Fuel Cell System That the Jet-Pump is Applied

Abstract

A fuel cell system is developed by applying a jet-pump system that performs hydrogen supplying and anode recirculation functions. The jet-pump system made up of an ejector and a proportional valve is designed to substitute conventional ejector-blower hydrogen recirculation system. The impulsive fuel feeding applied to overcome the ejector performance limits in low-power conditions. The fuel supply valve moves like injector to operate ejector at a design point in short time and does not works in remain time of each period. Therefore, average performance of ejector is better than continuous fuel feeding condition. The jet-pump compares aerodynamic performances with the blower and installed in the 100kW fuel cell system also. As a result, 25Hz and duty 75% conditions show above 80% of ejector-blower performance under 10kW emulation condition and three conditions demonstrates better performance over 10kW condition. Applicability of Jet-pump is verified at fuel cell system also. The system integrated jet-pump maintains stable state and shows equal level of ejector-blower applied case in Min. cell ratio and voltage decrease test results.