Sharing ideas on how to make a more efficent motor using Flyback (MODERATED)

[verpies]

Yes-odd how the current shot up as soon as the voltage inverted,which would seem like the switch off time.

Yes, it does seem like the switch-off time.
I suspect this odd current waveform is caused by improper scope probe positions.

Can you take a look at this schematic and let me know if you can spot the ground clips of the scope probes, appearing on this schematic around point B ?   ...or are they too small?

[gotoluc]

The video is marked as "Private" and I cannot watch it.
Which circuit and probe positions were used to make these scopeshots?  The current flowing through a coil cannot suddenly jump up like on that annotated scopeshot below !

Also, is Ch2 inverted?

The video is now public, sorry about that.

Link to video: https://www.youtube.com/watch?v=K8kwdrHCyig

The circuit is as below.
I inverted Ch2 to keep the scope shots looking like the previous or else the voltage would be inverted to the current. Do you want to see the voltage inverted to the current?

Luc

[gotoluc]

The current flowing through a coil cannot suddenly jump up like on that annotated scopeshot below !

That's just noise from the mosfet having a hard time switching off. See close up below.
I also included a non inverted scope shot with magnet rotor to coil.

Luc

[verpies]

The circuit is as below.
I inverted Ch2 to keep the scope shots looking like the previous or else the voltage would be inverted to the current. Do you want to see the voltage inverted to the current?

Inverting Ch2 was a nice touch.  I knew it had to be done to keep up the trace appearances with these probe placements, but I did not want to overwhelm you with suggestions.

[tinman]

The midpoint current might only show a difference when the coil's length is comparable to 1/2 of its driving wavelength and standing waves form -  read this.

At frequencies appearing in motors - this is a non-issue as they can be treated as lumped-element systems, in which the current is distributed uniformly along the coil.

It will read the current flowing through both coils if you drive it end-to-end.

Rather than say both coil's,lets just see it as one coil where a 1 ohm CVR is tapped into the mid point of the turn number. Anyway,lets say the DUT is my circuit on the other thread-the SSG circuit. In this case,the CVR that is in the center of the coil windings should read a higher average current flowing through the coil than that which is flowing into the coil--where that current is also viewed by way of another 1 ohm CVR.
Correct?.


Brad.