Pump-Less Recirculation System Derived from Electrical-Fluid Analogy for Proton Exchange Membrane Fuel Cell

Abstract

Unreacted fuel expelled from the outlet of fuel cells should be recirculated back to the inlet if wastage of the fuel must be minimized. Conventional recirculation systems employ mechanical pumps that consume electrical power and generate vibration and noise. This paper derives the pump-less recirculation system based on the analogy between electrical and fluid circuits. Concept of a switched capacitor circuit which is commonly used in electrical circuits was applied for recirculation in the fluid circuit. Operating characteristics and long-term stability of the proposed fuel cell system were experimentally demonstrated.