Magluvin is the first to contribute with these comments:
>>>>>>>>>>>>>>>>>>>>> MAGLUVIN FIRST COMMENT >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Its a boost converter.
When the battery is put across the coil, current begins to flow. As it flows, a magnetic field is built in the coil, and as the field builds, more current from the battery is taken.
When he disconnects the battery from the coil, the magnetic field collapses, causing currents to continue to flow through the coil, through the diode and into the cap, as it is the only short path available once the red wire is disconnected.. Mind you the current in the coil never changes direction. Wink
Didnt I do pages of this stuff at ou?
Tuff one.
Mags
>>>>>>>>>>>>>>>>>>> MAGLUVIN SECOND COMMENT >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Well how deep does the rabbit hole go?
More surface talk.....
Another possibility is, that I can only assume what orientation the diode is in, which determines the way current can flow through it.
Even if we reverse the diode, we still get our high voltage to the cap, but it is opposite polarity now.
When we charge a coil as shown in the vid, the field builds, and when we disconnect the source from the coil, that field collapses.
If we have a perfect switch used to connect and disconnect the source to the coil, meaning when on its on, but when off it will not allow current to flow, not even HV spark, then when we disconnect(open switch) the "forward" voltage of the collapse has only the path of the diode to charge the cap of my previous description of the vid.
What if we dont have a diode and cap? With our perfect switch, when we open it, the field collapses. And as it collapses down toward zero field, there is no place or path for the voltage potential produced by the collapsing coil to go.
Coils have capacitance. So the combination of coil with built in capacitance we have an LC. Single wire coils have very small capacitance between windings, and bifilar coils have a higher capacitance.
If you charge up an LC and disconnect, it will oscillate. So when we disconnect the source from our coil with no diode and no cap, our coil will oscillate at very high freq due to very small capacitance in our coil. The oscillation dies pretty quickly. No oscillation occurs if we have a path for that potential to the cap. The oscillation will be heavily damped
So if we reconnect our diode and cap, only we reverse the diode, when the source is disconnected from the coil, and the field collapses. But with no where for a continued forward potential current to flow, the coil goes into its oscillation mode, and the field collapses very quickly, and when the field polarity of the coil reverses during oscillation, N S to S N, that is when the potential of the coil has a path for current through the diode and to the cap for storage.
This is what I call back emf. In my original description, I call it forward emf, meaning that when we disconnect the source from the coil, the collapsing field current is in the same direction as the current produced by the source through the coil. In this reversed diode description, once the field of the coil reverses within 1/4 wave of LC oscillation, then the output of the coils current is in the opposite direction of the original source current. Back emf.
The output to the cap in either situation will be nearly the same. Possibly a small, tiny, itiy bitty, difference due to the bemf version may have lost some due to the dying oscillation during that 1/4 wave of oscillation mode, being that the oscillation eventually dies. So there is some loss in each cycle.
There are some out there that use the term bemf when actually to be correct in some situations, should use just emf or forward emf, produced by the collapsing field of a coil.
Well, im beat. Dont really have time to edit errors.
Magsleeps soon
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