A couple of comments are warranted from the snippets of QSO that
were reprinted earlier:
At 11:45 PM -0400 10/24/01, 2@vc.net wrote:
>// Regulation is not the reason for using a resonant-choke filter. With
>a capacitor filter, the peak current is c. 10x higher on the electric
A choke filter alone would also do. Or getting heavier service
installed for such problems. For systems which may have the load
removed and don't want giant chokes on L input filters, the resonant
approach offers voltage regulation better than large swinging chokes.
An L input filter (which limits inrush during the rectification cycle)
degenerates into a capacitive input filter when the L is too small to
reach critical value at light load current. There is a significant
rise in voltage when the capacitor charges to peak. This is
unregulated....
At 11:45 PM -0400 10/24/01, Jim, VE7RF was quoted as writing:
> >To get from 5% ripple down to <1% is a piece o
>>cake with a simple cap input filter + a 3 phase diode/plate
> >xfmr setup.
That's a fact - with 3 phase full wave rectified power supplies,
there is very little reason to use a big C or a big L since the
ripple voltage is already that low. Unless you have extreme phase
unbalance! So the inrush current is also low. 3 phase makes
transmitter designers much happier. Suprising that Collins used a 3
phase supply AND a resonant filter.
73
K5PRO
John
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