Experimental consideration on DC-DC converter circuits for fuel cell hybrid electric vehicle

Several researches on fuel cell hybrid electric vehicle (FCHEV) have been conducted in order to reduce greenhouse effect gas. One of the electric powertrain of fuel cell electric vehicle consists of fuel cell, rechargeable energy storage device, boost chopper and bidirectional chopper. The smaller size of the power converter on fuel cell hybrid electric vehicle is expected. Thus, interleaved configuration has advantage in converter size. This paper shows driving characteristics of an interleaved boost chopper connected to fuel cell and of a bidirectional chopper connected to electric double layer capacitor (EDLC). It is required that the bidirectional chopper is controlled by control method which considers state of charge (SOC) on EDLC. This paper proposes a control method which considers SOC on EDLC, and shows driving characteristics of the choppers for FCHEV in three states. As results of experiment, it is verified that two DC-DC converter converters can be operated adequately. In order to verify the power flow in three states in FCHEV, it is necessary to limit current value or duty ratio and to propose control method which considers SOC on EDLC.