Forward converter

When the switch turns off, the stored magnetic field collapses and the energy is transferred to the output of the flyback converter as electric current.

The flyback converter can be viewed as two inductors sharing a common core with opposite polarity windings.

In contrast, the forward converter (which is based on a transformer with same-polarity windings, higher magnetizing inductance, and no air gap) does not store energy during the conduction time of the switching element — transformers cannot store a significant amount of energy, unlike inductors.

[1] Instead, energy is passed directly to the output of the forward converter by transformer action during the switch conduction phase.

The forward converter is typically used in off-line supplies to provide an intermediate power output level of 100–200 watts.