How to design a coupled inductor with auxiliary winding ?

[Patrick66]

Hello everyone, can anyone teach me how to design a coupled inductor with auxiliary winding? Is the auxiliary winding considered multiple output loads since it uses two windings for the secondary side? If possible can someone share links that I can refer to. Thank you in advance guys for the help.

[Konkedout]

I think that your question is too broad and requires a textbook answer.  The whole textbook.

I think you might get more/better responses if you narrow it down to something specific you want to do.  Give all the numbers and requirements you can think of.

[RJSV]

   Guessing a bit, but what comes to mind is that you could wrap a primary side using something like 40 turns, using a steel or ferrite rod.
   Then, a magnetically coupled secondary wrapped on top, after some insulating sheet goes around primary.  I think you are asking about putting a third winding that would be simply wound, again, but not electrically connected, to either of the other windings...(?)

[jonpaul]

Power supply? RF amplifier? RF Oscillator?

Voltge? Waveform? Frequency? thruput power W VA?

Jon

[Jwillis]

Coupled inductor is to general of a term.
Coupled inductors are essentially transformers. This can also included common mode chokes and topologies used for converters. Coupled Inductors for converters have  a variety of Topologies such as  SEPIC (Single Ended Primary Inductor Converter), Flyback, Flybuck,  Buck-Boost (CUK), ZETA, and multiphase. Each of which would have their own winding configurations and applications . What type of Coupled Inductor and application are you interested in. 

[Patrick66]

Hello everyone, I'm thinking of designing a flyback convert with auxiliary winding to supply the IC controller for constant output current regulation in LED driver. Here are my parameters, Vin = 220 - 260 Vac, Vout = 78V, Iout = 0.35 A, Maximum Pout = 27.3 W. Hope to hear from you guys.

[johansen]

Take the volts per turn on the transformer and multiply by the volts you need for the controller.

Some fine tuning is needed especially for the 100 to 265v input supplies.

You need enough volts for the low end but not so many you burn up the zener at high line voltage

[Patrick66]

Can I use the equation from the attachment below to design my auxiliary winding ? Can I use the equations from the attachment below to design my transformer?