Author Topic: WFC Not Over Unity  (Read 12513 times)

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Re: WFC Not Over Unity
« Reply #8 on: December 13, 2012, 01:16:48 am »
I was using 1.5 inches squared which = 0.0381 meters squared

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Re: WFC Not Over Unity
« Reply #9 on: December 13, 2012, 01:22:43 am »
You must think in meters than it will work i'm sure. it worked for me... mind that 1cm is 0,01meter so 1cm2 = 0,0001 m2

In you first calculus 0,038m = 381cm2 way a lot =)

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Re: WFC Not Over Unity
« Reply #10 on: December 13, 2012, 01:27:26 am »
It was such a mystery to me but only now I had the clarity of mind to understand it..

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Re: WFC Not Over Unity
« Reply #11 on: December 13, 2012, 02:07:48 am »
ok so like this example for Stan's VIC Transformer core?
tw = 1.09728 cm
hw = 4.72186 cm
bf = 6.25348 cm
tw = 1.09728 cm

A = ( hw * tw ) + (2( bf * tf))
A = ( 4.72186 * 1.09728 ) + (2( 6.25348 * 1.09728 ))
A = ( 5.181203 ) + (2( 6.86182 ))
A = ( 5.181203 ) + ( 13.72364 )
A = 18.904843 cm2

2 * 18.904843 = 37.809686 .....I multiplied by 2 since there are 2 core halves

37.809686 * 0.0001 = 0.0037809686 meter2

Flux = 0.3 * 0.0037809686
Flux = 0.0011343

Primary Turns = ((12V / 0.0011343) / 5000)
Primary Turns =   10579.21185 / 5000
Primary Turns = 2.1158

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Re: WFC Not Over Unity
« Reply #12 on: December 13, 2012, 02:49:47 am »
No tony sorry you maybe misread it, i meant cross-sectional area not the total area of the core... only the cross-sectional area is considered here.

for example:
typic flyback core like... 1,8cm diameter
cross-sectional area 2,54x10^-4 m2
max flux= 7,63x10-5
12v 5khz = 31 turns considering bmax = to 0,3tesla which should holds true for up to 10-20khz

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Re: WFC Not Over Unity
« Reply #13 on: December 13, 2012, 02:52:53 am »
so what would it be using the measurements I gave for Stan's transformer?

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Re: WFC Not Over Unity
« Reply #14 on: December 13, 2012, 06:20:36 am »
well the cross-sectional area is tf multiplied by the component length in the z direction which you did not provided...

the area of interest is only the area of the wire loops you see? i mean the area of the core cut.

If meyer was using ferrite, this would mean for 2cm wide maybe 1cm high is 0.0002m2

so maximum flux would be 0,00006 webber considering bmax = 0,3 tesla

So turns number considering 12v 5 khz

40 turns...

If he was using a core that has half this size in high for example than it would be a flux of 0,00003

so turns = 80

so is directly proportional to the core size... I guess his core was smaller...

« Last Edit: December 13, 2012, 07:48:08 am by sebosfato »