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I am having a slight confusion regarding the flow of the currents in the push-pull and full-bridge during the dead time. Considering a push-pull converter during the ON and dead time.

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In the push-pull converter during the ON time of the MOSFET the current flows and the inductor and the capacitors at the secondary both charges and stores energy. During the off time, the inductor is a source of current for the load and the current flows as shown. I know that this is the stored energy of the inductor but still this current causes a flux in the secondary and primary should also have some current flow and voltage developed then. But since the circuit is open due to mosfet therefore there seems no current to be flowing. But we do have a body diode in the MOSFET... Can we say that the current flows due to the body diode?

In the full bridge this situation also occurs during dead time when all the mosfets are turned off.
Kindly help me in this slight confusion as I want to know what exactly happens, there are many different possibilities coming in my mind, but I want to know what exactly happens.

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I know that this is the stored energy of the inductor but still this current causes a flux in the secondary and primary should also have some current flow and voltage developed then. But since the circuit is open due to mosfet therefore there seems no current to be flowing.

Just because the secondary (now acting as the primary) has a current flow due to the diminishing current in the output inductor, it doesn't mean there is current flow in the primary (now acting as the secondary).

The current flow in the secondary induces a voltage in the primary and need not create primary current unless there is a conduction path.

Think about a regular transformer connected to a regular AC supply (but with no load on the secondary); there is a primary current flowing that causes the secondary voltage to be induced but, there is no secondary current unless we place a load on the secondary.

As an aside, in your particular circuit, the stored energy in the secondary inductor will circulate current through both secondary diodes and, because they are connected to opposing secondaries (see the dots), there is no net flux created in the core from these currents. This means no induced voltage on the primary.

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    \$\begingroup\$ Got it. Ive also heard that during the dead time the magnetic flux of the primary collapses, is it true?? Since there is no path for the current to discharge in my opinion the flux shouldnt collapse... \$\endgroup\$
    – kam1212
    Oct 28, 2023 at 10:17
  • \$\begingroup\$ @kam1212 the magnetic flux of the primary is also the magnetic flux of the secondary so, you can't really distinguish between the two. Hence, if the primary circuit is electrically disconnected, any (common or core) flux remaining has to be dealt with by the secondary (else a big voltage or back emf occurs). \$\endgroup\$
    – Andy aka
    Oct 28, 2023 at 11:31

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