half bridge Smps wave forms .....

[aniket87]

hi ,
i have built a half bridge smps with pfc front end for 2 X 200W class - D . it works fine but the wave forms that i see is troubling me .... Can any one have a look and tell me if i am doing it wrong ..... the smps has a open voltage loop . wat is troubling me is primary waveform at 90% load the wave form should be flat during the dead time which it is not ....


regards
aniket







Protel_Schematic.pdf

 

[indulis]

And during the dead time... how is the secondary current circulating?

Now, if that current were to flow through the secondary winding (changing flux), how would it reflect to the primary?