Re: Saturation in transformers.



Ian Iveson wrote:

> Daft Phil wrote
>
> >> No.
>
> > ** It is of no interest to transformer users to know what the
> > saturation current level is unless the applied voltage and
> > frequency is specified. Since Imag always increases with
> > increasing applied voltage, that is the practical way to view
> > t - especially when the transformer is intended for connection
> > to the AC supply.
>
> Rubbish. And how would you know what is of interest to any
> transformer user other than yourself. Where did I say transformer
> users *are* interested? And what is the rest of the paragraph
> for...are you arguing with yourself? What about?
>
> I am a transformer user, and I am interested in saturation current.
>
> And what's it got to do with "No" anyway...
>
> > Saturation is non-linear behaviour, it cannot be analysed from a
> > model that treats the primary as a simple inductor.
>
> >No kidding? Who said anything about a simple inductor? But it can
> >be usefully envisaged as an iron-cored inductor (which it is...you
> >can't hope to be taken seriously if you don't know a transformer is
> >an inductor, clot) in parallel with the reflected secondary load.
>
> It is useful to do so, regardless of how complicated the inductor,
> because it reveals why the current due to the load does not lead to
> saturation, whereas the current through the inductor can.
>
> Note that the usefulness of this model has nothing to do with the
> simplicity or otherwise of the inductor you envisage.
>
> In any event, models and analysis are both *always* simpler than
> reality. Otherwise there would be no point in using them.
>
> > Iron cored inductors are designed to behave linearly up to some
> > current figure - no such thing applies to AC supply transformer
> > primaries.
>
> Er...what babble is this? Hands up anyone who knows what you think
> you might be on about.
>
> cheers, Ian

I don't know whether you have ever examined the current wave forms in a
tranny
hooked up to a variac.
But its not very linear with applied voltage; and becomes
very non linear at the onset of saturation when the Bmax of around
1.5tesla
is reached.

Anyway, by examining the current wave form, and its phase relationship
and the distortion one gets some idea of what is happening in a typical
tranny.
Placing 4.7kohms in series between the low Z of the variac
drmatically increases the source impedance and the distortion
dramatically increases.
GOSS in the form of a toroid minimises the Dn, but it is informative to
do the experiments to really
see what goes on.

A dual trace CRO is almost essential to see the phase relationships.

Patrick Turner.



.

Relevant Pages

  • Re: Transformer attenuators
    ... that you can rely on the transformer also for the role ... "Core saturation happens when the magnetic field in the ... the applied voltage polarity remains the same ... talking about limiting the LF response, which means a high pass filter. ...
    (rec.audio.tubes)
  • Re: Saturation in transformers.
    ... "Ian Iveson" = Autistic Fuckwit ... >> current level is unless the applied voltage and frequency is specified. ... And how would you know what is of interest to any transformer ... >> that treats the primary as a simple inductor. ...
    (rec.audio.tubes)
  • Re: Saturation in transformers.
    ... > t - especially when the transformer is intended for connection ... I am a transformer user, and I am interested in saturation current. ... > model that treats the primary as a simple inductor. ...
    (rec.audio.tubes)
  • Re: Transformer attenuators
    ... that you can rely on the transformer also for the role ... about the possibility of ensuing distortion. ... "Core saturation happens when the magnetic field in the ... the applied voltage polarity remains the same ...
    (rec.audio.tubes)
  • Re: Transformer attenuators
    ... and this may be used to limit the LF response. ... use a transformer then arguably you don't need the ... "Core saturation happens when the magnetic field in the core ... the applied voltage polarity remains the same for a ...
    (rec.audio.tubes)