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Electronics/phase relationship


In my basic electricity books, I understand what they teach about the current laging by 90 degrees in an inductive circuit, and vis a versa for a capacitance. What they seem to be remiss in teaching the question of- what is the lag in an inductance that has been induced by a magnetic field. Let us suspose a magnetic field passes the end of a coil as in a generator or the field of the primary windings induces a current into the secondary windings. Is the current and e.m.f. in phase in this instant rather than when being pushed thru one end of a coil or capacitor? So, can I expect the phases between current and e.m.f. to be in phase coming out of my wall socket?

A generator is quite a different matter because the coils are used for producing electric current not reacting in a circuit. There are phase qualities within a generator but if you look at the equivalent circuit for a generator under load you will find the resistive and work element swamp out the magnetic coil effects.

Same story for transformer windings; they are power delivery systems and the equivalent circuit, again, the inductance is swamped out.  The analysis of RLC circuits is quite different from generator and storage devices.  

You can study these things in a good electric motor or transformer book.  The analysis is quite different from ac circuit theory.

Have fun.  


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Electronics questions about AC, DC and digital theory.


Graduate electrical engineer with over 40 years in electronic design, manufacturing, project organization and patent review. Experience in fields of industrial and consumer electronics (audio, video, acoustics, etc.)

IEEE (Institute of Electrical and Electronics Engineers); Senior Life member AES (Audio Engineering Society), Fellow Life member

BSEE University of North Dakota

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