| Abstract |
Based on the conventional forward converter, the
transformer’s magnetizing inductance is made small, and a
reset winding of the transformer is moved to the secondary
side, and furthermore, the anode terminal of the freewheeling
diode is connected at a different point. Then a novel topology
of DC-DC converter is proposed, and its power efficiency is
predicted to be improved. This converter has both operations
of forward and flyback manners, and both of two diodes in
the output side are maintained to be ON for a portion of the
switching period. This operation results in the zero ripple of
the output inductor current. This novel converter is
confirmed to have some prominent features of withstandvoltage
reduction for the main switch and ripper reduction of
the output inductor current. As a result, this converter
obtains a higher efficiency over the conventional forward
converter. This paper describes its basic operation, and
analyzes the steady-state characteristics by means of the
extended state-space averaging method. The analytical results
are confirmed experimentally, and an experimental result of a
high efficiency of 94% was obtained for the input voltage of
140V and the output load of 18V and 4A. |
