The forward converter is a DC/DC converter that uses a transformer to increase or decrease the output voltage (depending on the transformer ratio) and provide galvanic isolation for the load.
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. Instead, energy is passed directly to the output of the forward converter by transformer action during the switch conduction phase.
The voltage conversion ratio is (ns/np)×D where D is the duty cycle of the mosfet ns is the secondary turns and np is the primary turns of the transformer.
In the example we have set the duty cycle at 50% and the ratio of ns/np is equal to 4 so with 50V in the input we expect that after the transients settle out to have 100V at the output.
If you want to change the duty cycle just change the
width of all voltage pulse sources (5% is 50% duty cycle and 10% is 100% duty cycle).