Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

which transformer winding is better?

Status
Not open for further replies.

yoosefheidari

Member level 5
Joined
Aug 31, 2013
Messages
91
Helped
0
Reputation
0
Reaction score
1
Trophy points
1,288
Activity points
2,051
i want to make a 12v to 220vac inverter and for transformer winding i need help.
which winding is better and has lower leakage inductance?
or do you recommend better winding type?
frequency is 50KHz and power is about 350watts
 

Attachments

  • inverter.jpg
    inverter.jpg
    189 KB · Views: 122

i did it but i have some problem
first lets describe my work
i bought a 400watt modified sine wave inverter and by add a EGS002 module , turns it to a pure sinewave inverter.
i test it with a 250watt load and it work perfecly for 1 hours but with one problem.
problem was output voltage which was 170vac under load.
so i decided change the transformer with a new one and i wind my own transformer(first post of this topic)
by changing transformer voltage issue solved and voltage was stable under 250 watt load at 220 vac.
but now i have new problem
under 250watt load dc-dc(12VDC to 310VDC) mosfets(push-pull) and transformer become exeteremly hot after 2-3 minute work.
original transformer uses 2+2 turn foil copper(1.7mm2) for primary and 48 turns(0.5mm) for secondary(like right hand in first post) on an EI30 core
my transformer uses 3+3 turn foil copper(2.2mm2) for primary and 95 turns(0.7mm) for secondary(like right hand in first post) on an ETD29/16/10

what do you think?what is problem?
 

With foil windings you may be getting more eddy current loss...maybe you need Litz.
Also, do you have a gapped core.?.and is your foil winding near it....it may be picking up its field and getting more eddy currnt loss
 
With foil windings you may be getting more eddy current loss...maybe you need Litz.
Also, do you have a gapped core.?.and is your foil winding near it....it may be picking up its field and getting more eddy currnt loss
you mean i cant wind with foil as perfect as original transformer?and therefore i get eddy current?
no ,my core dosn't have gap.
so it seems i should try litz winding. i'm gonna use 9 wire in parallel(0.5mm) but there is one question.for better result and best coupling how i wind them ?
1-all 9 wires strands together?
2-each 3 wire in strands and then wind this 3 strands next to each other?
3-dosn't strands wires and wind them next to each other(flat)
4-your idea!
 

If you add another set of primaries to the outer on the sketch on the left - you will have better performance again. ( lower leakage by almost a factor of 2 ).

signed - an engineer who designs these transformers all the time ...


--- Updated ---

also each primary should be both wdgs wound bifilar and brought out to their respective terminals - this will reduce the pri to pri wdg leakage and give you much better results when you turn a mosfet off - esp at 50kHz, and 30 amps.

( you will see this later on when you power it up )
 
If you add another set of primaries to the outer on the sketch on the left - you will have better performance again. ( lower leakage by almost a factor of 2 ).

signed - an engineer who designs these transformers all the time ...


--- Updated ---

also each primary should be both wdgs wound bifilar and brought out to their respective terminals - this will reduce the pri to pri wdg leakage and give you much better results when you turn a mosfet off - esp at 50kHz, and 30 amps.

( you will see this later on when you power it up )
you mean using wire instead of foil is not nessecory?which you recommend at this current rating?
i didn'exactly get your points.can you explain visually?or give me pdf that explain these points?
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top