Hi Dave,
> > It makes no difference if the rectifiers are full wave.
> >
> > The caps charge from both rectifiers 120 times per second in the
> > USA, and 100 in countries who have slower dynamo's. 73, Tom W8JI
> > w8ji@contesting.com
>
> Sorry, but I don't agree with that statement either Tom. Why do you
> think 3-phase rectification has lower ripple than single phase ? If
> one bridge is starting to provide less voltage to the caps, as another
> one is providing more, the average voltage will be higher, and so the
> ripple less. If you draw it out, I'm sure you would agree.
Where are you getting the phase shift? There is no phase shift
(unless the supplies are three phase, and transformers are on
separate phases) between the transformers.
You can have an inversion, but that is all. Even the inversion does
not mater with full-wave rectifiers...and with half-wave you'd just
need to reverse the primary or secondary on one transformer.
You seem to think a conventional power transformer adds
noticeable phase delay. It does not. It can not.
> *If* you could get the two transformers out of phase by 90 deg, and
> rectified that with two full wave bridges (on one each transformer),
> you would get the caps replenished at 2f (120 Hz in the USA) from one
> bridge, and 120 Hz from another, *but at different time*. Hence the
> caps get replenished at 4f (240 Hz).
Did you leap to three phase without telling anyone? Even if so,
where does 90 deg come from??? Maybe if you try to describe a
transformer that has or can have 90 degrees phase shift between
primary and secondary, that will help.
73, Tom W8JI
w8ji@contesting.com
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