How to coil a transformer

[hongv]

I have a ETD49 3C90 transformer and i am thinking of amplifying a 20Vac to 1000Vac. 20Vac is from a half bridge converter and the switching frequency is 27KHz, output current is 20mA. Is it possible to coil it? thanks

 

[hongv]

anyone willing to share? thank you!

 

[alabpro]

tranformer desing
http://schmidt-walter.fbe.fh-darmst...s_e/smps_e.html

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www.alab-pro.com

 

[Claus]

That address dosn't seam compleate.

 

[richie00boy]

If you have the following data for the core then you can use a formula/spreadsheet I have (will dig it out):

cross sectional area (mm^2)
flux density (mT)

 

[alabpro]

transformer desing
http://schmidt-walter.fbe.fh-darmstadt.de/smps_e/smps_e.html

----------------------------------------------------------------------------------
www.alab-pro.com

 

[hongv]

The effective area is 211mm^2 and the minimum area is 209mm^2. The B is 200mT at 25KHz.

I read the article but i am not very sure about the Vin_min and the Vin_max. if my supplied voltage is 20Vac peak to peak, what is the Vin_min? Vin_max is 20?

I read some articles saying that insulation is needed after every layer of coil and epoxy is added. Then cannot coil it from one end to the other and coil it back again.... do i need to cut the wire after a layer of coil then isulate it and continue again?

Thanks so much for replying..