Maybe possible idea for duplicating effect of Holcomb and others

[Feb2006]

Have a look at this patent application that Solarlab talked about a while ago.
If it works it could maybe be better than Holcombs.

[citfta]

Why isn't that creating a short with your ground probe on the positive of the power supply? I'm a little confuzzled.

Hi Jim,


Any time you are working with motor control circuits you MUST make sure your scope is isolated from the AC mains ground.  I don't know anything about the power system in Australia so I can't advise how to do that.  Here in the US we either use a 1 to 1 isolation transformer or a short extension cord with the ground pin removed.  Of course when working with real motor controls the ground pin of the scope can be a hundred or more volts above earth ground so you MUST  be very careful to not make any connections when the circuit is live.


Thanks to you and the other's who are working on this.  Together who knows what we might accomplish.


Take care,
Carroll

[Jimboot]

Hi Jim,


Any time you are working with motor control circuits you MUST make sure your scope is isolated from the AC mains ground.  I don't know anything about the power system in Australia so I can't advise how to do that.  Here in the US we either use a 1 to 1 isolation transformer or a short extension cord with the ground pin removed.  Of course when working with real motor controls the ground pin of the scope can be a hundred or more volts above earth ground so you MUST  be very careful to not make any connections when the circuit is live.


Thanks to you and the other's who are working on this.  Together who knows what we might accomplish.


Take care,
Carroll

thanks Carroll, I've been measuring across g&d . I thought there must be an isolated ground looking at ufo vid. Enjoy your trip

[citfta]

Hi Ufo.


Thanks for posting the screen shot of all 3 phases. I have been studying it some and I think I understand how it works.  Next week I will be back home and after I get the circuit built I will have a better idea about it.  I think we can clean up the signal some.  We might have to leave a little of the spiking in there as that might be part of the triggering process.


Thanks again,
Carroll


PS: Went down to the Swiss Alps today.  Germany is certainly a very beautiful county.

[bistander]

Hi Ufo.


Thanks for posting the screen shot of all 3 phases. I have been studying it some and I think I understand how it works.  Next week I will be back home and after I get the circuit built I will have a better idea about it.  I think we can clean up the signal some.  We might have to leave a little of the spiking in there as that might be part of the triggering process.


Thanks again,
Carroll

I've been wondering about the spikes. Was going to suggest using a free wheeling diode (FWD) across each phase winding. That would certainly reduce the V spikes, but could interfere with the primitive sequencing method. The lack of FWDs and high gate resistance (slow turn-on) causes a lot of device heat (losses). It's a neat little build, but unlikely to be practical in a 'real' device.
bi

Wonder how ariovaldo is doing with his VFD?