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Symmetric DC-DC power transformer

Started by Unknown June 13, 2020
I am working on a dual active bridges (4 mosfets instead of 4 diodes) by switching directions using either: 555, CPLD, FPGA or micro, depending on timing complexity.  In the simplest case, just a 555 switching primary and secondary at the same time.  In more complicated case, a micro switching with turn-on delay T1, turn-on time T2, turn-off delay T3 and frequency F1.

What are the estimated efficiencies with:

1. T1, T3 = 0
2. T1, T3 <> 0

For instance, 20 degrees T1 to ramp up magnetic field on the primary, 140 degrees to drive secondary and 20 degrees to ramp down.

What would be the best F1 for driving a microwave transformer at around 12V?  Perhaps outside audio range to avoid humming.

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When 40% of the population makes less than US$150 a month, one of the 2nd tier leader is worth US$500M.
Can't name the specific country, or this could be censored or be attacked from down under by proxy (or Bill).

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3. Communism: people must suffer for the leader's worth
4. Cashmunism: only cash matter, nothing but the cash

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Capitalism at it's best (or worst).
The dual active bridge topology uses LLC transformer

Using an advanced topology like this combined with the request about a microwave transformer makes no sense from my humble point of view 

You cannot get the correct leakage inductance in this case and ZVS ZCS is not possible 

Using those simple drive circuits you might better go for a HB topology with synchronous rectification 

Better is to wind your own transformer if you insist on using DAB

Cheers

Klaus
On Monday, June 15, 2020 at 5:59:17 PM UTC-7, klaus.k...@gmail.com wrote:
> The dual active bridge topology uses LLC transformer > > Using an advanced topology like this combined with the request about a microwave transformer makes no sense from my humble point of view > > You cannot get the correct leakage inductance in this case and ZVS ZCS is not possible
OK, i will look into getting LLC transformer.
> Using those simple drive circuits you might better go for a HB topology with synchronous rectification
What above just driving it at a narrow range of one side? For example: let Vi be input voltage, Vx be 0.2Vi, Vj be Vi + Vx, Vk be Vi - Vx Drive input at Vj, Vk, Vi, Vk, etc. My concern is saturating the core.