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Re: [femm] how do I model a torroidal transformer ?
Come on guys. This is easy.
The attached file shows you how to do this.
Remember this is static, not dynamic. But this
will work fine for getting the field. This would
be a no load condition. For a loaded case you
would have to calculate the rate of change,
figure the voltage induced and the current based
on the load. Depending whether the field is
rising or falling in the primary you can determine
the Lenz reaction polarity accordingly to oppose
or assist the primary drive. I will leave that
up to the user to handle all the other details.
The main trick is to use point currents for the
coil windings. Just run the attached file.
David Meeker can fill you in on any other way
to do this. But this is one way.
DRS
robert Macy wrote:
> The torroidal transformer *is* axisymmetric, but when drawn
> that way the currents go around the small circle and the
> magnetic field is perpendicular to the page. I don't think
> femm solves this situation.
>
> Instead and approximation is to draw the cross sectional
> view in x-y form and set the total length to the median
> circumference.
>
> The "crunching" of the field at the inside curve won't show
> up, but it will get you started.
>
> - Robert -
>
> On Mon, 25 Aug 2003 03:16:32 -0000
> "Dr Mark Snoswell" <mark@xxxxxxxxxxxxxxx> wrote:
>
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>>How do I model the field of a torroidal transformer? ...
>>it's axi
>>symetric but I can't quite see hwo to model it.
>>
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