Hi Marv,
Do you remember which kind/type of rectifier diodes you have been using ?
Did do some research and found some ultra-fast diode's (trr < 30ns) with
decent reverse voltage (600V), but would be interested in your experience
? Suppose the "chopping" freq of the SMPS would be in the moderate range
of 10-40 KHz ?
Thanks, Carel.
>
> Hi Paul,
> I conjured up a simple solution for winding that style of transformer a
> while back.
>
> "Standard" Teflon isulated wire is typically rated for 600 volts. The
> 3KV rated stuff is too thick.
>
> Instead, run two #22 teflon insulated wires through some #12 teflon
> tubing. Then, parallel as many of these assemblies as necessary for
> the required secondary voltage and feed them all through tubular
> copper braid which will become the primary. A piece of woven
> fiberglass tubing, typically used in under the hood automotive wiring,
> over the outside completes the assembly.
>
> This single cable is then wound around the core(s).
>
> I connect the pair of wires from each teflon tube in series; then to
> individual 1KV fast diode bridges.
>
> These bridges are then connected together to create the output voltage.
>
> With 380 volts on the primary, 8 secondary runs (4 tubes) are good for
> 3KV.
>
> The only disadvantage of this scheme is that all the extra insulation
> does need more core window area than would typically be required.
>
> Incidently, that '91 QEX article is overly heavy on the core side. A
> few more primary turns will greatly reduce the core cross section
> requirement. At these frequencies and power levels, almost any core of
> the correct material and large enough to accomodate the windings will be
> adequate.
>
> 73 & Good afternoon,
> Marv WC6W
>
> http://wc6w.50webs.com/
>
>
>
>
> --- On Wed, 3/11/09, Paul Decker <kg7hf@comcast.net> wrote:
>
>> From: Paul Decker <kg7hf@comcast.net>
>> Subject: [Amps] HV PS transformer
>> To: amps@contesting.com
>> Date: Wednesday, March 11, 2009, 9:02 AM
>> GM gents,
>>
>>
>> Part of my (3cx800A7) amplifier project is to do something
>> "new". Well OK, it's old, but new to me.
>>
>>
>>
>> I'm trying to reproduce the switch mode power supply
>>
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