Electric Motor Secrets

[lighty]

It's a good thing protection diodes are doing their job or you would now have instantly fried MOSFETs.

Anyway- simply adding resistor would very probably compromise frequency response of your probes and with such sudden impulses and short periods that could mean erroneous measurement. The only real solution would be to acquire higher attenuation probes.

For now you could go to your software and Util->Measurement->Voltage->Peak to Peak and the soft will do measurement for you. You can also use other functions there like RMS measurement and other stuff. At time domain measurement you can measure rise time and other factors if you ever plan to test another coil configuration.

In my experience the voltage you're getting is probably in the range between 470-550V because otherwise protection diodes would get very hot in short time.

So for now leave everything as is and have fun with recovery circuit. In case you're using capacitor it would be advisable for it to have it's breakthrough voltage rated on 600V or more just to be on the safe side.

As for the protection diodes sinking excess energy- don't worry as soon as you route energy anywhere else they won't open anymore. Check out and you'll see that they'll be stone cold.

[Jetijs]

Hi all
Lighty, I did everything as you instructed. I used a laptop on battery for the measurement time. I got two scope shots, the first one is from the probes across source and drain of one of the MOSFETs. The other shot is from the recovery coil and recovery diode:





I set the probes to the highest voltage divider setting there was - x10. Also in the software I set everything to x10 and the highest possible voltages. I then unchecked the green and yellow waveforms leaving only the red one, as you said. You can see, that the voltage across the MOSFET source and drain goes off the limits. If every square is set to be 50 volts, then this means that the voltage goes way over 400v. At the second image we can see in the upper part some sort of ringing. For this test I used the one IN4007 diode on the recovery coil. If I run the motor without load, the amp draw increases a little and the protection diodes start to get slightly warm, so they are doing their job

So is there any way how I could see the full voltage spike? Maybe I should use a resistor in series with the probes?
Thank you
Jetijs

[Jetijs]

Thanks lighty for the guidance
I just sent you the whole software so you can install it and check everything out by yourself.
I will make those measurements this evening and then post the results.
Thanks.

[lighty]

You cannot have any load connected to recovery diodes. You must measure unaffected signal because battery, capacitor or any other device will effectively "suck up" all of the released energy and you won't get any usable measurement of the voltage spike itself. So, disconnect everything from the diodes and measure signal between free end of recovery coil and recovery diode.

Also, check out that both ground clips on your probes are connected together and not with anything else. If possible use laptop on battery power in order to prevent any ground influence on measurement.

I'm not familiar with your scope software since I usually use Tektronix DSOs but I will help as much as I can based on the screenshots you've posted.

So, forget about FFT as for the moment we don't need to know the spectral content of your inductive discharge impulse.


So do the following:

1. Disconnect battery or anything else from the recovery coil.
2. Start up everything and measure signal between drain and source of MOSFET. If the voltage spike seems like it's suddenly cut out between 450-500V that's because protection diodes are doing their job. Also, if the protection diodes starts to get even lukewarm it means they're doing their job. So, the voltage in this case is above 450-500V and in that case we'll have to worry about not burning your scope. However, this doesn't mean protection diodes will interfere with our intended recovery because those protection diodes will have to act only in case your recovery circuit doesn't do it's job. So, nothing to worry about for the moment if the voltage spike is under the protection diodes turn on threshold and in that case proceed to point 3.
3. Connect differential probe between free end of recovery coil and free end of recovery diode.
4. Set up probes voltages to the highest possible value (we'll probably deal with few hundred volts) in software. Also, set voltage divider on your probe to x10 or higher (just to be on the safe side- we don't want to burn your scope).
5. Set frequency to 20MHz (2kHz is way too low for such short impulses). I hope that's the frequency of bandwidth limiter because as I said I'm not familiar with your software controls.
6. When you're measuring if you get all three signals represented your software should be capable of omitting representation of both channels on screen and showing only the differential signal (the red one). So try un-checking CH1 and CH2 selections. If the software is standard one you should now see only the red waveform. If not you'll just have to ignore the green and yellow ones.


Also, could you please send me User manual for your software or if you don't have it could you then send me a Help file from your installation (CHM file most probably) so that I could check out other inner settings of your scope we could possibly set up like sampling rate and possibly RMS measurement of the represented math form.

BTW- thx for posting screenshots- please do that in the future as well so that I can see what you're getting. I'm pretty certain Peter would be interested as well.

[Jetijs]

Lighty, do you mean that I should connect both scope probes across the output battery terminals? If so, then would I even see any spikes? Because when I put the scope across the charging battery on a Bedini SSG, I could see only a more or less straight line of 12 or so volts and very small peaks (in milivolt range) at the SSG produced frequency. I mean, the battery absorbs all the spikes and I only can see the full spike voltage if the charging battery is removed, but as we know, that can damage the transistors or in this case the MOSFETs.

So, I set my scope software to a demo mode with simulated sinewave at 2kHz on both probes. Now I set the math to A-B (I think) and a third waveform appeared in red (see the picture) it is almost flat. Is this the right way?

http://www.emuprim.lv/bildez/images/viskautkas_labs/visadi_strunti_1/math.jpg

Also, I went through the help file of the software and the word RMS was mentioned only in one part. If I go to the FFT menu, I have this window:

http://www.emuprim.lv/bildez/images/viskautkas_labs/visadi_strunti_1/rms.jpg

And the "help" explains what the different measurements mean:

-SNR (Signal to Noise Ratio): The ratio of the amplitude of the fundamental frequency to the Noise.

-ENOB (Effective Number of Bits) : The number of bits in an ideal converter that would be required to give the same SNR performance.

-SINAD (Signal to Noise and Distortion):The ratio of the amplitude of fundamental frequency to the Noise, but Noise include Harmonics.

- THD (Total Harmonic Distortion): The ratio of the RMS sum of the harmonics to
the RMS value of the fundamental.

-SFDR (Spurious Free Dynamic Range): The ratio of the RMS signal amplitude to the RMS value of the peak spurious spectral component. The peak spurious component may or may not be a harmonic.
: The RMS value of the peak spurious spectral component.

-Total Power: The RMS value of the sum of all spectral components.
: Sum of Noise excluding DC and Nyquist.

Which one do I need to look at to get the RMS value?
I haven't dealed with these kinds of measurements before
Thanks.

[lighty]

@Peter

It is my pleasure to help. I don't have any spare time to make one motor myself but it's interesting to help and see where it goes. Thank you for publishing this design.



@Jetijs
When you're finished dealing with mechanics could you please connect ground of your two oscilloscope probes together (so you don't use that common ground but rather two "live" inputs), set A-B (A minus B) channel mathematics in your software and possibly use ungrounded laptop instead of desktop PC (run it on battery without power cord). Also, don't forget to set sampling rate as high as possible and bandwidth also to max (turn off any filtering if you have it). Differential probe should really give you some advantage when measuring inductive collapse event for numerous reasons I won't go into for the lack of time and ungrounded laptop should greatly reduce effects of grounding when measuring these extremes. So, use two recovery diodes I've sent you (connected in series just to be on the safe side before we know what's the value of voltage peak) to "rectify" and measure the voltage spikes maximum value as well as RMS value. It would be beneficial to know these values in order to possibly calculate optimum value of the recovery capacitor. Also, it's good to know what you're dealing with before you possibly use lower rating parts and burn them. The voltage won't go over 500V on the power side because of the protection diodes you used but in future if the voltage is possibly too low one can use higher number of turns on the recovery coil (with appropriate corrections of wire gauge and other parameters of course).

[elias]

Great work!

Jetijs,

I have been following your progress, and I am hoping very much for you to achieve great results out of this. Eager to hear about your amount of recovery and other experiments!

Thanks for sharing your progress.

Elias

[Peter Lindemann]

I Concur

Good work Jetijs.

Jetijs,

Great work. Seems like the motor can really hum along. As for your back side batteries, they seem pretty dead. You may want to get a battery to charge that is equal to the run battery, or move to the "recycle to the front" circuit and see how much the current drops.

What I do is set up the front end with the capacitor and the blocking diode, and then connect some wires with alligator clips to the output. That way I can quickly connect the output to a light bulb, a second battery, or back to the capacitor on the front, and study the behavior of the motor in each case.

Lighty,

Thanks for helping Jetijs with the MOSFET drive circuit. I really appreciate your expertise and willingness to help.

Peter

[lighty]

Good work Jetijs.

[Jetijs]

Hi Steven,
I am sure that the problem was the lockup. After increased air gap I never had a problem like this again As for the RPM's, I also think, that the motor sounds slower, because with my previous design I got 2600 RPMs at best and it sounded WAY faster. I put a black tape on the shaft so that it covers half of the shaft diameter, and then I just pointed the laser tachometer on that spot, it showed about 1800. I will try to verify this with a scope.
Thanks,
Jetijs

[nali2001]

Comments

Hi Jetijs,
Looking good! So any idea yet what the real problem was? The switching or a rotor lockup? T

his is no criticism, but you sure that is 1800? Does not really 'sound' like it. How do you measure rpm?

Keep us updated!
Great work.

Regards,
Steven

[Jetijs]

There is already a thread about that in this forum:

http://www.energeticforum.com/renewable-energy/984-coral-castle-ed-leedskalnin.html?highlight=leedskalnin

This thread is only for discussions about Peters attraction motors.
Thank you for understanding,
Jetijs.

[ANTIQUER]

Ed Leedskalnin & Magnitricity

If you have never heard of Ed you should check him out. He apparently figured out anti-gravity and the universal way electricity works. I saw a PBS documentary on him several years ago. HE BUILT A CASTLE COMPLEX NEAR Miami,Fl. by himself using anti-grav. to move huge blocks of coral (up to 30 tons!) by himself. He also moved it one time and loaded these huge stones on a flat-bed semi truck by himself using only one hour per load. His theory is fascinating & sems to work. Might help solve everyone's problems with electric current. You can check him out at Mystic Places.com for a start. By the way he was from Latvia.

[Jetijs]

Ok, after hours of soldering I finally finished my MOSFET circuit. After this I don't want to see the soldering iron again for a long time
Everything works beautifully, the amp draw is about 1.6A at 12V. The RPM's are about 1800. The motor vibrates alot so I will have to balance the rotor. The commutator wheel in these first tests has the same 40 degree gap on each side. Here is a video:
YouTube - Lindemann attraction motor V2.0 video 4
I will make more tests and measurements tomorrow.
Thank you,
Jetijs

[Jetijs]

Hi all,
I as you know, my transistor circuit fried, so I decided to give the MOSFETs a try since I already received all the parts needed from lighty
Lighty was so kind and guided me through the MOSFET circuit basics. So far I only tried this circuit on one phase and it works really well, the MOSFET does not heat as much as transistors did and the motor runs much faster at one phase than it did with the transistor circuit using two phases. The torque is very great, at least in the firing position, you can not hold the shaft with your hands in the fire position. I will get some soldering plates and solder all this together and then I will post my results. Here is the circuit I will be using:



I would like to thank lighty for his help and patience with me

Thanks,
Jetijs