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

[Yttrium]

re: others doing similar work.

This guy was exploring along similar lines :

https://www.youtube.com/channel/UCpcT7LePUsT8nkTS614_7ew

Discussion of it here, not a well-informed discussion judging by the first couple of pages of arguing, name-calling and all the usual crap that gets in the way :

http://overunity.com/12147/this-might-blow-your-mind/#.VoKlXlLq-vg

I'm still searching for the experiments that were almost exactly along the line Luc et al are following.


Y.

[verpies]

@ Verpies
Got some HCF4047BE

I was on the road when you posted this...

Below is a schematic depicting how you can use 4 of these chips to make a motor pulse sequencing circuit (warning: U3 is wired differently from the others).
If you do not need the "Discharge C" output signal, then just use only the first two chips (U1 and U2).

Calculate the capacitors (C1 - C4) according to the pulse widths that you want (or delays you want) using the formula below:

C = t / 595
where the time (t) is given in ms
..and the resulting capacitance (C) is in μF

For Example: If you need the pulse width (or delay) to be 10ms then the relevant capacitor should be 0.017μF , ...because 10/124=0.017
Of course 0.017μF = 17nF.
If you don't have an exact capacitor that you've calculated, then put the closest one you have and adjust to the desired pulse width (or delay) with the corresponding potentiometer (multi-turn pot recommended).

[Magluvin]

Something odd Im finding with my electric bike motor setup.

At the time I had shown the waveforms I had shown that wide open throttle there was no pulse width modulation happening, where it was just switching battery power to the coils in their respective phases. Then when I backed off the throttle some, the pwm kicks in and varies a shorter turn on pulsingas you throttle down.

Well while riding recently I noticed something odd.  All this time, 8 yrs, I never really seen it till now.  When ridding full throttle, no pwm, the bike will get up to full speed on flat road. But if I back off the throttle, about 3/8 in, it went a bit faster. I can feel it if I gauge it while in acceleration also.

At first I thought it was the magnet in the throttle going too far past the hall sensor. But when I lift the wheel off the ground and do the scope shots, full throttle is wide open no pwm. 

Could it be that while in the highest power pwm state before going full no pwm, that it provides more motive force to the wheel than wide open no pwm???

Strange but true.

So the next test will be to ride with one of my tiny scopes connected to see if things are the same as I think they are.

Mags

[gotoluc]

Thanks for the circuit verpies.
If I understand the circuit correctly, the discharge is to activate a mosfet to dump the flyback cap?... if so, why would we want to do this during Energize L on time?   would it not always be after L is opened and flyback has charged the cap?
Speaking of flyback, what will activate the mosfet to capture flyback so I can get rid of the diode to make it more efficient?  would pin 11 be fast enough to do this?   also, keep in mind that I've got lots of MIC4451YN (attached pdf) which I think have two out that are inverted. Could this also work and should I use them to trigger all the mosfets?

Thanks for your help

Luc

[gotoluc]

Something odd Im finding with my electric bike motor setup.

At the time I had shown the waveforms I had shown that wide open throttle there was no pulse width modulation happening, where it was just switching battery power to the coils in their respective phases. Then when I backed off the throttle some, the pwm kicks in and varies a shorter turn on pulsingas you throttle down.

Well while riding recently I noticed something odd.  All this time, 8 yrs, I never really seen it till now.  When ridding full throttle, no pwm, the bike will get up to full speed on flat road. But if I back off the throttle, about 3/8 in, it went a bit faster. I can feel it if I gauge it while in acceleration also.

At first I thought it was the magnet in the throttle going too far past the hall sensor. But when I lift the wheel off the ground and do the scope shots, full throttle is wide open no pwm. 

Could it be that while in the highest power pwm state before going full no pwm, that it provides more motive force to the wheel than wide open no pwm???

Strange but true.

So the next test will be to ride with one of my tiny scopes connected to see if things are the same as I think they are.

Mags

That's interesting Mags

Maybe when the PWM kicks off the motor cores go above the max saturation point which would actually weakens the motors torque output.
If you can change your gear ratio so your motor can turn at a higher RPM, it may deliver max torque at full throttle.
To me it sounds like your motor is bogged down with too much of a load and that may be corrected with a gear change.

Does it make any sense to you?

Luc