DETAILED DESCRIPTION An embodiment of the invention is shown in FIG.
2, wherein 10 refers to a main transformer having primary windings 12 and 14, a core 16, and secondary windings 18 and 20.
Windings 12 and 14 have equal turns, oppositely wound as shown by the conventional dots, so that primary currents (I.
sub.
p1 and (I.
sub.
p2) produce opposite flux in core 16.
Windings 12 and 14 are fabricated such that there is minimal parasitic capacitance and leakage inductance between windings.
Power is supplied from a DC source 22, bridged by capacitors 24 and 26, which serve to remove ripple and also provide a stable source of power for the converter.
Windings 12 and 14 are connected in parallel across the input voltage 22.
In series with winding 12 is a control switch 28; in series with winding 14 is a control switch 30.
Switches 28 and 30 are operated alternately, by the control circuit shown in FIG.
6, and with a predetermined delay or dead time between the opening of one switch and closing of the other.
Switches 28 and 30 are mosfets having intrinsic diodes 32 and 34, respectively, which clamp the voltage swing after the opposite switch turns off.
The delay time is effected by, inter alia, designing a predetermined parasitic capacitance into the control switch means 28, 30, 32, 34.
The main transformer 10 is designed such that the magnetizing current will be great enough to charge the parasitic capacitance of the Primary windings 12, 14 in a controlled fashion.
Magnetically linked, by the core 16, to the primary windings 12 and 14, are secondary windingS 18 and 20, wound to phase with the windings 12 and 14 as shown by the dots.
Inductances 36 and 38 are not discrete circuit elements, but represent the leakage field of the windings 12, 14, 18, 20 reflected into the secondary.
Output from the secondary is rectified by any suitable means, exemplified here by diode 40 in series with winding 18, and diode 42 in series with winding 20.
Output from diodes 40, 42 is tied to the output terminal 44, as shown at 46
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Fuel Cells 
