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Re: Sync 200BPS improvement, (short post !)
In a message dated 99-07-24 05:51:11 EDT, you write:
<< At 01:23 PM 7/23/99 -0400, you wrote:
>In a message dated 99-07-23 05:46:29 EDT, you write:
>
>
> Snip....
> >I think maybe non-sync operation ruins the power
> >factor in general? (due to the chaotic and unstable inductive kicking
> >and bucking) :)
> >
> >Cheers,
> >John Freau
> >
> Hi John,
> While working on MMC RMS current calculations, I ran into this. Sync gaps
> are always able to fire at the high point of the AC cycle so they waste
> very little available power. However, non sync gaps are firing at random
> places on the AC cycle. Thus they are very often firing at less than
> optimal voltage. I ran some calculations on this and found that a 120BPS
> asynchronous gap will only deliver 1/2 the power of a 120 BPS sync gap due
> to hitting at less than the optimal time. I use a power correction factor
> that is 1 for a sync gap and 1/2 for a non-sync gap in MMC calculations to
> account for this. In order to recover this lost power with a non-sync gap,
> you need to run at 240 BPS or higher. Of course, in that case, you need a
> more powerful charging circuit than a neon too... A 120 BPS non-sync gap
> appears to be a waste of time given that an equal sync gap will double the
> power throughput...
Terry,
In the non-sync rotary tests I was refering to, I was running at higher
break rates of around 500 BPS, and was powering the system with
a pole pig. Have you done any simulations of the power factor for
such a situation?
I agree that a 120 BPS non-sync gap system is undesireable.
Cheers,
John Freau
Cheers,
Terry >>