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

[gotoluc]

I expected 80% "backspike" energy recovery efficiency.

Both 10% and 125% are surprises to me

Me too!... I thought my big ass low resistance coil would do better. Apparently not

I'm going to have to change to hall sensors to clean up my switching spike problems.

Luc

[itsu]

Does this overunity "backspike" energy recovery efficiency also occur when the rotor is stopped?

I think so as i  do not see much difference when running or stopped, see this post:
http://overunity.com/16167/sharing-ideas-on-how-to-make-a-more-efficent-motor-using-flyback-moderated/msg468976/#msg468976

The average input power is pretty useless (just like the RMS current) unless it is measured only during the ON-pulse.
Does your scope have the ability to do measurements between cursors, or do you have to manipulate the display to show only the part of the waveform that you need to measure?

Ok,   no no posibility to measure power between the cursors, so i manipulated the display to show only the "on" time, see screenshot 1 below.
Its negative as the purple trace is on the negative part, so i inverted the purple trace in screenshot 2

Both situations are when running at 40Hz @ 18% duty cycle  (12V)
Remember, i use here the 0.1 Ohm csr

Thanks,  regards Itsu

[verpies]

Me too!... I thought my big ass low resistance coil would do better. Apparently not

I don't think that your big ass low resistance coil is the problem.
It is much more likely that your C2 or D1 are the problem as well as your wiring (no-starpoint).

I'm going to have to change to hall sensors to clean up my switching spike problems.

A high R_DS-ON MOSFET transistor could be the culprit, although 6A is not a big deal for most MOSFETs today.
The gate timing seems to be fine, and Hall sensor will not improve it.
My McGyver circuit would improve it, but without these CD4047 chips it is very hard to get the LM3915 Vu-Meter to work as a sequencer...but not impossible

[verpies]

Ok,   no no posibility to measure power between the cursors, so i manipulated the display to show only the "on" time, see screenshot 1 below.

I remember that your previous ON-pulse was almost 8ms wide but now the entire screen spans 4ms.  Why?

[itsu]

It must be because of a lower speed and/or duty cycle.
This pulse motor when externally synced has a life of its own, sometimes it just won't run at the max 555 timer pots settings meaning 40Hz @ 18% dc, so i settle for a lower speed/dc to have some data taken.
I therefor try to mention the speed/dc each time.

Itsu