Experimental Investigation of a High Efficiency Power Path Controller for PEM Fuel Cell and Battery Hybrid System

Nowadays, study on alternative sources of fossil fuels for power generation has attracted great attention. Polymer electrolyte membrane fuel cells (PEMFCs) have higher energy densities and lower power densities than the conventional batteries. PEMFCs should be hybridized with battery to increase the stability without decreasing the maximum power. Typically, DC-DC converters are utilized to combine these systems leading to significant increase in cost, size and weight of system; however, using these converters reduces system efficiency. In this paper, a circuit is implemented for PEMFC and battery hybridization system with a power path controller. The experimental investigations covers the main challenges in the PEM fuel cell power system implementation concerning current ripple and electric power changes dynamics. This circuit implementation leads to increasing system efficiency over 95 percent and decreasing the cost by at least 50 percent. The hybridization circuit is verified by simulation and experimental results.Keywords: PEM Fuel Cell, Lead-Acid Battery, Hybridization Circuit, DC/DC Converter, Switch.