Re: Self Tuning Resonance Mosfet Half Bridge transformer

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Sam Doughty by way of Terry Fritz <twftesla-at-qwest-dot-net>" <sdman.sam-at-gte-dot-net>

Vladi,

Sorry for the late reply, been on a short trip.
Thanks for the info on the Self Resonant power supply.
I have been looking for a self resonant low voltage power supply
for a high power audio amp (+85,-85) either half-bridge or full using
two mosfets. I came across a schematic a few years back but can't remember
where I saw it, been looking the last month but haven't able to find it. I
remember it used a Diac for triggering and two IRF450 mosfets. Also
it used a soft switching technique for lower noise and transient
suppression.
I have seen your type of circuit or topology being used in power supplies
for flourescent lamps. Thanks again for your help and if you come across
or have any info on this topology would appreciate it very much if you would
let me know.

Regards,

Sam Doughty



----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Friday, March 15, 2002 5:57 PM
Subject: Re: Self Tuning Resonance Mosfet Half Bridge transformer


> Original poster: "vladimiro mazzilli by way of Terry Fritz
<twftesla-at-qwest-dot-net>" <mazvla-at-iol.it>
>
>
>
> Tesla list ha scritto:
>
> > Original poster: "Sam Doughty by way of Terry Fritz
<twftesla-at-qwest-dot-net>"
> <sdman.sam-at-gte-dot-net>
> >
> > Where can I get info on building the Self Tuning Resonance Mosfet Half
Bridge
> > transformer? I found the schematic but no xfm building info, guys name
was
> > Mazzilli
> > Vladimiros.
> >
> > Sam
>
> Sam, there's no xformer,  the HB switches drive directly the primary coil.
> The voltage fed
> resonant converter throught the diac pulse, bring the sistem near
resonance
> of Lprim,Cres circuit
> (the mosfet are driven by the current at the output of the center of HB).
> The contribution of
> secondary carried on primary inductance seems to be low because the weak
> coupling coefficient,
> but I've tried with several type of secondary an the operating frequency
> changes in order to have
> a solid flame in output and the object placed near the streamer seems to
> have no effect on output
> power, and is not necessary to retune the oscillator like the IC's driven
> TC often require.
>
> Cheers
>
> Vladi
>
>
>