Serious HES derivative project proposal

[citfta]

Hi again Bi,



You're getting forgetful.  We had this discussion a few months ago.  But here is the video I posted before in the other thread showing the induction into the rotor of the alternator.


https://ugetube.com/watch/OTyaKIHaevI6co9


You can go back to the general builders section and look for the thread called " possible idea for virtual magnetic field" to refresh your memory.


Carroll

[bistander]

Hi again Bi,



You're getting forgetful.  We had this discussion a few months ago.  But here is the video I posted before in the other thread showing the induction into the rotor of the alternator.


https://ugetube.com/watch/OTyaKIHaevI6co9


You can go back to the general builders section and look for the thread called " possible idea for virtual magnetic field" to refresh your memory.


Carroll

You're right citfta, forgetfulness comes along with age. Thanks for the memory jog. I recall now. But rotation with slip rings open circuit meant the rotor iron had induced current and behaved as an induction motor. I'm still having trouble visualizing how that causes varying flux thru the rotor core in the center of the field coil. Getting too off-topic. Might have to scavenge and play with an old car alternator.
bi

[kolbacict]

Regarding using a VFD powered by DC we need to see what the actual signal looks like.  Here is a video I did and posted in my thread about a moving virtual magnetic field.

I  look from my VFD this. I hoped to see  something better.

something more like sinus. Do you see the same?

[bistander]

I  look from my VFD this. I hoped to see  something better.

something more like sinus. Do you see the same?

Yet it seemed to produce the RMF.

I see much different PWM with the VFDs that I've scoped. They use a carrier frequency in range of 2 to 20 kHz, or pulses per second.
bi

https://electrical-engineering-portal.com/download-center/books-and-guides/automation-control/induction-motors-pwm-frequency-inverters

[kolbacict]

Yes you are right. Here is my oscillogram from the current shunt of one of the phases.

p.s. Who deletes my messages here, it's not easy for me to write them in English.
It costs you nothing to write thousands.
How kind you are.