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Author Topic: TinMan Generator Research Moderated Topic  (Read 148630 times)

Jimboot

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Re: TinMan Generator Research Moderated Topic
« Reply #165 on: July 26, 2015, 10:31:29 AM »

Thanks Erfinder.


A few things I've learned today.
I used one of my pulse motor circuits to drive the motor. Pretty ordinary performance.
I shorted the stator coils using a reed. Not much joy there. Lowered the output.
On the upside I found that with more area of the brush making contact the greater the output and therefore lower current draw ( I love that new law)


My motor unloaded draws about 2.1A loaded 1.5A . That's having the stators in series. More speed does not necessarily equal more output. Now i think I need to go and get a washing machine :)




gyulasun

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Re: TinMan Generator Research Moderated Topic
« Reply #166 on: July 26, 2015, 11:21:43 AM »
Not sure why my last post(like Luc's last post) is highlighted as a quote.?

Hi Brad,

It remained as a quote because there must have been a   /quote  symbol left as the last line and you started your answer above that last line.  Just place that symbol above the line of your answer, using the Modify icon on the right side of your post.


Regarding the schematic on Luc's setup:  I think the input DC voltage going to the brushes is interrupted by a MOSFET so that the rotor coil is between the drain of the MOSFET and the input positive battery rail, and the MOSFET is controlled by a function generator between the gate and the source pins.  The positive rail goes to the lower brush of the motor as shown in the video and the flyback diode is connected to the upper brush which is also the drain of the MOSFET, as I see it in the video.

EDIT  the    /quote    symbol is embraced with these two brackets of course:  [ ] 

Gyula

tinman

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Re: TinMan Generator Research Moderated Topic
« Reply #167 on: July 26, 2015, 12:03:15 PM »
Hi Brad,

It remained as a quote because there must have been a   /quote  symbol left as the last line and you started your answer above that last line.  Just place that symbol above the line of your answer, using the Modify icon on the right side of your post.


Regarding the schematic on Luc's setup:  I think the input DC voltage going to the brushes is interrupted by a MOSFET so that the rotor coil is between the drain of the MOSFET and the input positive battery rail, and the MOSFET is controlled by a function generator between the gate and the source pins.  The positive rail goes to the lower brush of the motor as shown in the video and the flyback diode is connected to the upper brush which is also the drain of the MOSFET, as I see it in the video.

Gyula

I have a feeling that what i consider to be flyback is different to what Luc considers to be flyback.
To me,in order to get flyback,or inductive kickback,the coil has to become open. As the coils on the rotor are all interconected,they can never become open to produce a flyback<-- as i know it to be.
I believe what Luc see's as flyback in this situation,i see more as being a stepup transformer action.

Anyway,i am surprised to see that cap charge up so high in his demo video.
It is good to learn something new. Now i will be interested to see if he can make it work without the PWM,and by adding that second set of brushes to catch this high voltage-!what ever it is!

gyulasun

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Re: TinMan Generator Research Moderated Topic
« Reply #168 on: July 26, 2015, 12:16:40 PM »
Hi Brad,

It is okay that you consider a coil  has to become open to get the flyback pulse across it just after interrupting the current in the coil.  It is also okay that in a rotor the coils are all in series ring so in this sense they are never 'open'  BUT consider the two brushes always see a certain L inductance which always consists of  two 'half circles', one on the left and the other on the right direction and these two 'half circle' of series coils are connected in parallel with each other as the brushes see them, ok?
So the result is that there is always a resulting L inductance towards the 'outside world'  and whenever a current is interrupted in any L inductance, the voltage spike occurs, no matter if there are shunting coils in parallel.  By the way the Teal patents deal with paralleled coils if I recall correctly.

Gyula

Grumage

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Re: TinMan Generator Research Moderated Topic
« Reply #169 on: July 26, 2015, 02:16:38 PM »
Dear All.

Brad's " Brush tipping " pictorially.

Automatic coil shorting ??   ;)

Cheers Grum.

tinman

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Re: TinMan Generator Research Moderated Topic
« Reply #170 on: July 26, 2015, 02:57:29 PM »
Dear All.

Brad's " Brush tipping " pictorially.

Automatic coil shorting ??   ;)

Cheers Grum.
Wrong coils.
But you did just show why the brushes arc ;)
Most believe it is from high voltage kickback,when it is in fact high current arcs produced by each coil being shorted by the brushes as you have shown.

tinman

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Re: TinMan Generator Research Moderated Topic
« Reply #171 on: July 26, 2015, 03:11:05 PM »
For your entertainment
As you will see,current causes the light show from the brushes,not voltage.
Voltage potential will only define as to how large the gap can be before !current! will begin to flow. As the gap between the brush and commutator segment will only be very small,the only a low voltage potential is required for current to flow.High voltage is also not required to see spark fly when hooking a clip lead to a wire as Luc suggested in his video.

https://www.youtube.com/watch?v=bGMMDBkf1RY

Grumage

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Re: TinMan Generator Research Moderated Topic
« Reply #172 on: July 26, 2015, 04:06:21 PM »
Wrong coils.
But you did just show why the brushes arc ;)
Most believe it is from high voltage kickback,when it is in fact high current arcs produced by each coil being shorted by the brushes as you have shown.

Dear Brad.

So are you saying that it would be better with Fig 2 ?

Cheers Grum.

tinman

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Re: TinMan Generator Research Moderated Topic
« Reply #173 on: July 26, 2015, 04:14:51 PM »
Dear Brad.

So are you saying that it would be better with Fig 2 ?

Cheers Grum.
Grum
The shorting of the coils via the brushes is somthing you cannot change-unless you make your brushes thinner than the gap between the armature segments. That shorting of the coils is actually good,as that is when you see the high voltage spike on the stator coil's,as a large magnetic field is produced from the rotor coil when the brush shorts that coil.

Here is a video where i am looking for the !so called! high voltage flybacks from the rotor coils.
As you can see on the scope-there is none,even though i can see the brushes arcing slightly. The arcs are from the brushes when they are shorting each coil-not from some high voltage arc,but from a high current due to the short.

I didnt get the second half of the video due to my PWM being fried. Will post it when it's repaired.
Enjoy the background scenery of my video from now on ;)

https://www.youtube.com/watch?v=VlRiXMR9VAE

poynt99

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Re: TinMan Generator Research Moderated Topic
« Reply #174 on: July 26, 2015, 04:15:14 PM »
For your entertainment
As you will see,current causes the light show from the brushes,not voltage.
Voltage potential will only define as to how large the gap can be before !current! will begin to flow. As the gap between the brush and commutator segment will only be very small,the only a low voltage potential is required for current to flow.High voltage is also not required to see spark fly when hooking a clip lead to a wire as Luc suggested in his video.

https://www.youtube.com/watch?v=bGMMDBkf1RY
To help resolve the issue, putting a scope on the coil in each case would speak volumes. Guess you posted while I was writing this.

gotoluc

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Re: TinMan Generator Research Moderated Topic
« Reply #175 on: July 26, 2015, 04:28:57 PM »
Luc
Could you please post a quick schematic of your inductive kickback circuit,as i cannot get anymore than the input voltage out of the brush contacts. The only way i see you getting that sort of voltage out of the rotor is by way of making your rotor coils act as a stepup transformer. For example,if you had 20 turns on your rotor coil,then applying 12 volts,then switching that 12 volts off,you should be able to get around 240 volts out.
Also,please understand that my answer is in relation to you placing more brushes on the rotor to collect the flyback.

Thanks.

Hi Brad,

please find the attached circuit. Last night after doing more test I found by adding a second diode on the other stator coil which I had left open in the last two videos it helped to lower the current.

I think this method of collecting Rotor flyback would be as good if not better than trying to make a dual brush system.
Keep in mind the rotor coil is being fully turned on and off multiple times during the time the brush is on each commutator segment and at the frequency and pulse width of your choice. So I think this would be better and offer more flexibility then a physical dual brush system.

I would suggest you add this simple component to your v.3 RT and you may find you can further lower the input power.

Luc
« Last Edit: July 27, 2015, 05:46:21 AM by gotoluc »

tinman

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Re: TinMan Generator Research Moderated Topic
« Reply #176 on: July 26, 2015, 04:40:59 PM »
Hi Brad,

please find the attached circuit. Last night after doing more test I found by adding a second diode on the other stator coil which I had left open in the last two videosit helped to lower the current.

I think this method of collecting Rotor flyback would be as good if not better than trying to make a dual brush system.
Keep in mind the rotor coil are being fully turned on and off multiple times during the time the brush is on each commutator segment and at the frequency and pulse width of your choice. So I think this would beet a dual brush system.

I would suggest you add this simple component to your v.3 RT and you may find you can further lower the input power.

Luc
Luc
You have included one of the stator coils,and that coil will become open when the mosfet opens.
I thought you wanted to know if you could collect a high voltage from the rotor only if you added more brushes to collect this mystery flyback from the rotor coils.
What i was trying to say(and have shown)there is no high voltage from the rotor coils just because you see arc's at the brushes. This voltage is very low,but the current flow is high when the coil is shorted by the brush.
You pulsing the coils is very different to using the brushes only,and trying to collect from that.To get any sort of higher end voltage,you would need some really crappy brush/armature contact.
« Last Edit: July 26, 2015, 04:59:08 PM by gotoluc »

gotoluc

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Re: TinMan Generator Research Moderated Topic
« Reply #177 on: July 26, 2015, 05:10:10 PM »
Brad,

I don't understand the confusion.

First,  fact, any coil will produce flyback when the power source is disconnected, so the rotor coils are not exempted.

Second, my idea to collect the rotor flyback was because the input current is outrageously high when only the rotor coils are connected, so I was trying to lower it by using something that is normally wasted.

Third, if the stator coils are separate from the rotor coils, then why not direct the flyback in them and see if it can assist the rotor.

Forth, it does work and better than I thought so why not consider using it?

Luc

Grumage

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Re: TinMan Generator Research Moderated Topic
« Reply #178 on: July 26, 2015, 05:13:56 PM »
Grum
The shorting of the coils via the brushes is somthing you cannot change-unless you make your brushes thinner than the gap between the armature segments. That shorting of the coils is actually good,as that is when you see the high voltage spike on the stator coil's,as a large magnetic field is produced from the rotor coil when the brush shorts that coil.

Here is a video where i am looking for the !so called! high voltage flybacks from the rotor coils.
As you can see on the scope-there is none,even though i can see the brushes arcing slightly. The arcs are from the brushes when they are shorting each coil-not from some high voltage arc,but from a high current due to the short.

I didnt get the second half of the video due to my PWM being fried. Will post it when it's repaired.
Enjoy the background scenery of my video from now on ;)

https://www.youtube.com/watch?v=VlRiXMR9VAE

Dear Brad.

Thank you for those educational videos.

Cheers Grum.

gotoluc

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Re: TinMan Generator Research Moderated Topic
« Reply #179 on: July 26, 2015, 05:23:50 PM »
I thought you wanted to know if you could collect a high voltage from the rotor only if you added more brushes to collect this mystery flyback from the rotor coils.

I knew before doing the test and obviously after doing the test that I can collect high voltage flyback from the rotor coils, irrespective of my original ideal of dual brushes. 

What i was trying to say(and have shown)there is no high voltage from the rotor coils just because you see arc's at the brushes. This voltage is very low,but the current flow is high when the coil is shorted by the brush.

Your test could not show the rotor flyback using just diodes. Attache a switch with a low pulse width with a flyback diode and the story will change.
I know the current is high and I now understand what your brushes are doing.

You pulsing the coils is very different to using the brushes only,and trying to collect from that.To get any sort of higher end voltage,you would need some really crappy brush/armature contact.

Not sure where you're going with this

Luc