Flux density rate of change is related to Voltage
V = dB/dt
and
V = L di/dt
So
dB/dt = L di/dt
Integrating both sides
B proportional to I
----- Original Message -----
From: "Phil (VA3UX)" <phil@vaxxine.com>
To: <amps@contesting.com>
Sent: Tuesday, May 07, 2002 7:33 AM
Subject: Re: [Amps] Rectifier diode strings
> At 08:31 PM 5/6/2002 -0700, you wrote:
> >Yes, that is what I thought also, Jeff. If the flux density doesn't
> >increase under load, then how is energy transferred from
> >primary to secondary?
>
> No, Tom is correct. Flux density is a function voltage, not current. If
you
> look up the voltage equation for transformers you'll see that current is
> not involved. Ampere-turns is what determines the mmf in the core.
>
> Flux density remains essentially constant at all loads.
>
> Phil
>
>
> >Mike, W4EF.....................
> >
> >----- Original Message -----
> >From: "jeff millar" <wa1hco@adelphia.net>
> >To: <W8JI@contesting.com>; "Ian White, G3SEK" <G3SEK@ifwtech.co.uk>;
> ><amps@contesting.com>
> >Sent: Monday, May 06, 2002 7:22 PM
> >Subject: Re: [Amps] Rectifier diode strings
> >
> >
> > > Whoa...flux density comes from Ampere-Turns, not Volt turns.
> > >
> > > But, overall an excellent discussion.
> > >
> > > jeff, wa1hco
> > >
> > > ----- Original Message -----
> > > From: "Tom Rauch" <w8ji@contesting.com>
> > > To: "Ian White, G3SEK" <G3SEK@ifwtech.co.uk>; <amps@contesting.com>
> > > Sent: Monday, May 06, 2002 2:12 PM
> > > Subject: Re: [Amps] Rectifier diode strings
> > >
> > >
> > > > > Unless I misunderstood Tom's point about mains transformers
saturating
> > > > > at 1.3-1.4 times normal primary voltage, surely that would only
apply
> > > > > at full load? The main risk to the rectifiers is more likely to be
> > > > > during RX periods, when the load is at a minimum but the DC
voltage is
> > > > > at a maximum. I don't believe the saturation argument would apply
> > > > > then, would it?
> > > >
> > > > Yes, saturation applies. Remember what it is. The core can only
> > > > obtain a certain flux density, and that flux density relates only to
> > > > the volt-turn of the magnetizing winding. Flux density is the same
at
> > > > full load or no load, ignoring small differences caused by
resistance
> > > > in the primary and power mains.
> > >
> > >
> > > _______________________________________________
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> > > Amps@contesting.com
> > > http://lists.contesting.com/mailman/listinfo/amps
> > >
> >
> >
> >
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