Hyungjoon Kim, Changwoo Yoon, Sewan Choi, “A Three-Phase ZVZCS DC-DC Converter for Fuel Cell Applications”
Abstract : In spite of having many advantages such as low
switch voltage and easy implementation, the voltage-fed DCDC
converter has been suffering from problems associated
with large transformer leakage inductance due to high
transformer turn ratio when it is applied to low voltage high
current step-up application such as fuel cells. This paper
proposes a new three-phase voltage-fed DC-DC converter
which is suitable for low voltage high current applications.
The required transformer turn ratio is as low as that of the
current-fed converter owing to ǻ-Y connection. ZVZCS for
all switches are achieved over wide load range without
affecting effective duty cycle. A clamp circuit not only
clamps the surge voltage but reduces the circulating current
flowing through the high current side, resulting in
significantly reduced conduction losses. The duty cycle loss
can also be compensated by operation of the clamp switch.
Experimental waveforms from a 1.5kW prototype are
Area of Interest : High Power DC-DC converter, Fuel Cells,
ZVZCS, Three-Phase DC-DC converter.