RE: DRSSTC driver tests- Dual resonance disaster

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "Jason Judd" <JJudd@xxxxxxxxxxxxxxxx>

I have just noticed on my DRSSTC that with the PLL disabled (used only
as an oscillator) the duty cycle changes through the burst making the
IGBTs switch as non zero timmings. This only happens with the secondary
in place and I suspect it is the field from the secondary/toroid causing
the problem. At first I thought is was an interaction between the
primary and secondary so I lowered the coupling, to around .1 , but that
didn't change anything.

I am going to try a TL494 to see if that is any more stable.

Jason.

> -----Original Message-----
> From: Tesla list [mailto:tesla@xxxxxxxxxx]
> Sent: Wednesday, 26 January 2005 10:53 AM
> To: tesla@xxxxxxxxxx
> Subject: Re: DRSSTC driver tests- Dual resonance disaster
>
> Original poster: Steve Ward <steve.ward@xxxxxxxxx>
>
> Steve,
>
> This might be a good opportunity to bypass the PLL and just
> run it straight off its feedback signal and compare.
>
> I assume you tried altering the coupling between your coils?
>
> Steve W.
>
>
> On Tue, 25 Jan 2005 08:14:18 -0700, Tesla list
> <tesla@xxxxxxxxxx> wrote:
>  > Original poster: "Steve Conner" <steve.conner@xxxxxxxxxxx>
>  >  > >I'll post an updated schematic tomorrow, and I'm also
> going to try driving  > >two coupled resonant circuits and
> see what happens. The PLL might not be so  > >happy with the
> dual resonance  >  > Well driving the dual resonators was a
> total disaster. It behaves  > chaotically and hops all over
> the place. I have no real idea what causes it  > to mess up
> so badly, but I intend to find out. It might just be
> something  > stupid or then again, it might be a fundamental
> flaw with the idea of using  > a PLL to drive two coupled resonators.
>  >
>  > I thought I better let you all know in case anyone was
> thinking my circuit  > was all tried and tested.
>  >
>  > Steve C.
>  >
>  >
>
>
>