User talk:Chevytech

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I , have after MUCH thinking about transformer EMF, decided to amend some of the prior comments I made regarding the generation

of EMF in the iron core transformer. I had referenced some previous work done on the subject, regarding the use of the Poynting vector in the energy transfer process of the transformer. I have, mistakenly thought that some form of "Flux Cutting" was responsible for the generation of an EMF in the iron core transformer. Several things come to mind that make it clear to me that I was, at least ,partially mistaken. If flux Cutting is responsible, then, in an unloaded transformer, the magnetizing current"H" flux wave would be the "cause" of the emf and the induced emf would have the same waveform of the magnetizing current. II DOES NOT. It has a sinusoidal waveform because the flux in the iron core is sinusoidal, not to mention that the strength of the supposed "flux cutting" H field would be far too weak to induce the emf seen in actual operation. Faraday's induction law says (in so many words) that if the magnetic flux in an iron core should change with time,the volume that is enclosed by the iron circuit will experience an induced non conservative electric field. That is exactly where the primary and secondary windings are, in that field. The thing that troubled me was the exact mechanism of induction, what, years ago in texts on the subject would refer to as the "seat" of induction. All of this can be traced back to Maxwell's work as well. I am of the opinion that the same "type" of induced emf happens in the "almost zero" flux region of the slot of an induction motor rotor. There is virtually no flux there, but an emf is never the less induced there with rotor rotation in the stator field, which will measure exactly the same if the rotor conductor (bar) would be moved to the top surface of the rotor, assuming the air gap flux remained the same with the same rotor RPM. Anyway, in a transformer on load, depending on the power factor of the load, leakage fluxes as well, that act as a choke in series with the primary and secondary windings. All of this is run of the mill transformer theory, I was confused about the actual induction process, trying, as many do to "make flux cutting fit". Flux cutting and flux linking are two distinct process of induction, not necessarily related. Sometimes it is a mixed bag as in the case of the alternating current induction motor, with flux cutting and transformer emf both at work at different times and different places within the motors electric and magnetic circuits. Sorry for the digression, just wanted to set things straight. Thank's,
CHEVYTECH 3/19/13