Wow Transients

[mbrownn]

I just had a wow moment. I took a 1.2kw 220v angle grinder with a damaged armature and disconnected the second field winding. I powered it with 20v AC and measured the signal on the scope. I noticed that there were some faint transients on the input signal at the peaks of the AC wave measuring at least 80v above the wave. I then put the scope on the unused winding and measured the signal. I was getting a very dirty signal of 8v AC giving me about 14 transients per sine wave of about 6 to 20v above the AC, except at the peaks where the transient was 160v and very pronounced. Much stronger signal than seen on the input coil.

The damage to the armature is a break in the winding so that it isn't a complete loop

My scope is an old analogue type

I took a pic with my cell phone but it is not very clear

The question is, Why are the transients bigger and more pronounced on the disconnected coil ?

The AC wave is obviously a transformer action between the powered field coil and the unpowered one and as expected the AC wave is of reduced voltage Most of the small transients were not visible on the powered coil but were strong and defined on the unpowered one. Usually the intensity of the signal on these types of scope is an indication of power in the spike but I wasn't expecting an increase in voltage and intensity of spkes from this unpowered coil

[mbrownn]

Second question, why are the transients so much bigger at the peaks of the wave? ie up to 20x when on the rise or fall it was about 2x

If you were looking to make transients and feed them to your source battery, placing a bridge rectifier on this would surely work although it is hard on the brushes.

The arcing at the brushes is reduced when a load is placed across the unused coil, this is known as inductive compensation.

[boguslaw]

I don't know if this is the same but I found that a 1:1 ferrite transformer can produce very high voltage spikes on disconnected secondary side . I thought it was like in Joule Thief but maybe not. 200v spikes from 12V input at 50mA.

I can charge 200uF capacitor to 200v or more quite fast in few seconds and I can find some resonant frequencies when the output spikes are more clear and stable but at other frequencies they are diffused.

Anyway it works at 18khz or generally in khz range with the ferrite generating some noisy sound (but at resonant frequencies it is more clear also) .
The only thing interesting was the 1:1 choke used for this , I didn't expected it but I know now that output of transformer can be made via Faraday law differently then based on turns ratio. Something like that was reported first by Tesla.


I apologize if this is a known method of producing DC-DC inverters , I'm not experienced in electronics.

I have btw also a question. I tried to connect a voltage multiplier to the output of transformer but only the first stage seems to work the second stage voltage is just a few volts higher. Is that because I used 22nF/1000V capacitors and they are too big ? Unfortunately I cannot check it now, I don't have other capacitors to check . I appreciate any comment or help and apologize if this is offtopic.

[mbrownn]

I don't know if this is the same but I found that a 1:1 ferrite transformer can produce very high voltage spikes on disconnected secondary side . I thought it was like in Joule Thief but maybe not. 200v spikes from 12V input at 50mA.

I can charge 200uF capacitor to 200v or more quite fast in few seconds and I can find some resonant frequencies when the output spikes are more clear and stable but at other frequencies they are diffused.

Anyway it works at 18khz or generally in khz range with the ferrite generating some noisy sound (but at resonant frequencies it is more clear also) .
The only thing interesting was the 1:1 choke used for this , I didn't expected it but I know now that output of transformer can be made via Faraday law differently then based on turns ratio. Something like that was reported first by Tesla.


I apologize if this is a known method of producing DC-DC inverters , I'm not experienced in electronics.

I have btw also a question. I tried to connect a voltage multiplier to the output of transformer but only the first stage seems to work the second stage voltage is just a few volts higher. Is that because I used 22nF/1000V capacitors and they are too big ? Unfortunately I cannot check it now, I don't have other capacitors to check . I appreciate any comment or help and apologize if this is offtopic.

You are on topic, I am studying the transformer effects in a motor.

Like you I am no expert so thanks for the tip on Faraday's law, I suppose it is like what happens in an ignition coil in a way but the ratio is 1 to 1.

I just put a neon on it and it blew out but it would not light a florescent tube

[mbrownn]

I think you hit the nail on the head with Faradays law creating transients but there is another effect too.

The armature and motor field coil are bucking to some degree and this could be a reason for the increase in voltage on the unpowered coil when compared to the powered coil.

JLN Labs - The TEP Project - Bifilar VS Bucking coils

In the motor the condition will be similar to the fourth setup on the above page, of course we are using AC and not square wave but notice how the transient is increased in size and duration when compared to the others.

Now I have to find an explanation as to why the effect is only at the crests of the wave.

[mbrownn]

I think it must be the same reason, because the fields of the coils are at their maximum when the transient occurs.

I just increased the voltage to 40 volts and I got the effect along most of the wave.

[Ufopolitics]

Dear MBrownn

I just had a wow moment. I took a 1.2kw 220v angle grinder with a damaged armature and disconnected the second field winding. I powered it with 20v AC and measured the signal on the scope. I noticed that there were some faint transients on the input signal at the peaks of the AC wave measuring at least 80v above the wave. I then put the scope on the unused winding and measured the signal. I was getting a very dirty signal of 8v AC giving me about 14 transients per sine wave of about 6 to 20v above the AC, except at the peaks where the transient was 160v and very pronounced. Much stronger signal than seen on the input coil.

The damage to the armature is a break in the winding so that it isn't a complete loop

My scope is an old analogue type

I took a pic with my cell phone but it is not very clear

The question is, Why are the transients bigger and more pronounced on the disconnected coil ?

The AC wave is obviously a transformer action between the powered field coil and the unpowered one and as expected the AC wave is of reduced voltage Most of the small transients were not visible on the powered coil but were strong and defined on the unpowered one. Usually the intensity of the signal on these types of scope is an indication of power in the spike but I wasn't expecting an increase in voltage and intensity of spkes from this unpowered coil

Hello MBrownn, nice to "see you" again,

By disconnecting one field of the stator motor, you are making an Asymmetrical Machine ...Therefore ALL Laws of Conservation of Energy simply do "Not Apply" (N/A)... anymore
The Primary (connected) Field starts some kind of "non symmetrical open induction" into the Secondary Field, this last one (2nd Field) by being open, starts to resonate its magnetic induced field from Primary, with the "Open Space", and, since absolutely nothing impedes from it to do so, as it no longer have a "killing reversed input" ...then it outputs those incredible spikes...

Second question, why are the transients so much bigger at the peaks of the wave? ie up to 20x when on the rise or fall it was about 2x

This Open Coil (Secondary Field not connected) is Resonating, Feed-backing from and endless source of energy...It will keep developing this Higher Signals "in crescendo" as You increase the Primary Input AC Pulses...
I have named this as "Negative Induction"...an Open, Asymmetrical Induction established between a pulsed Coil response action with the Open Space...the Vacuum...the Aether...

The arcing at the brushes is reduced when a load is placed across the unused coil, this is known as inductive compensation.

When you place a load on the non connected, resonating Coil...it establish some kind of reverse network communication with its "feeder" (the Primary Coil), demanding more "Positive Induction" in order to keep generating its new Load now is demanding...therefore, the Primary now has "Two Jobs" to perform:

1- To keep machine rotating
2- To feed secondary positive induction...

Therefore, diminishing the excessive arcing at brushes.
There is more to this...
I believe, (not sure because have not done the additional testings necessary as to be "completely" sure) But, I believe this reverse connection from secondary (not connected coil) to Primary, (connected) also allows the back flow to Primary of some of the Resonating Field Energy...
If you have time, measure Voltage across Primary as you load the Secondary...


I know...You now for sure...May think I have gone "completely" insane...

But am ok...

Regards

Ufopolitics

[mbrownn]

Hello MBrownn, nice to "see you" again,

By disconnecting one field of the stator motor, you are making an Asymmetrical Machine ...Therefore ALL Laws of Conservation of Energy simply do "Not Apply" (N/A)... anymore
The Primary (connected) Field starts some kind of "non symmetrical open induction" into the Secondary Field, this last one (2nd Field) by being open, starts to resonate its magnetic induced field from Primary, with the "Open Space", and, since absolutely nothing impedes from it to do so, as it no longer have a "killing reversed input" ...then it outputs those incredible spikes...


This Open Coil (Secondary Field not connected) is Resonating, Feed-backing from and endless source of energy...It will keep developing this Higher Signals "in crescendo" as You increase the Primary Input AC Pulses...
I have named this as "Negative Induction"...an Open, Asymmetrical Induction established between a pulsed Coil response action with the Open Space...the Vacuum...the Aether...



When you place a load on the non connected, resonating Coil...it establish some kind of reverse network communication with its "feeder" (the Primary Coil), demanding more "Positive Induction" in order to keep generating its new Load now is demanding...therefore, the Primary now has "Two Jobs" to perform:

1- To keep machine rotating
2- To feed secondary positive induction...

Therefore, diminishing the excessive arcing at brushes.
There is more to this...
I believe, (not sure because have not done the additional testings necessary as to be "completely" sure) But, I believe this reverse connection from secondary (not connected coil) to Primary, (connected) also allows the back flow to Primary of some of the Resonating Field Energy...
If you have time, measure Voltage across Primary as you load the Secondary...


I know...You now for sure...May think I have gone "completely" insane...

But am ok...

Regards

Ufopolitics

Not sure, you may have something or maybe not.

I have just been examining the spike more closely, It raises up 5v above the AC and has many small spikes of a volt or so above that then curves up into the huge spike. On the way down it also curves out much as it would with inductive kickback. No obvious oscillation as shown by JLN.

My gut feeling on this is that as the commutator draws an ark we get this 5v raise in voltage and as the arc breaks the voltage shoots up. on the way down it acts like inductive kickback until it drops to the voltage of the AC wave.

Of course the mirror image occurs on the negative side of the wave.

I will do the load test tomorrow as its 2am here

[mbrownn]

The voltage across the primary does not change as far as I can tell by loading the secondary but I do get increased current draw. I can't tell if I am getting a change in speed or torque at this voltage and I don't want to increase the voltage much as my variac won't take the current draw, plus the brushes are arcing more with increased voltage causing damage.

So at this point I am concluding that there is significant transformer actions in this motor setup. One is a normal transformer action transferring the AC as we might expect and one is an apparent increase in the transient voltage (and possibly power) due to a bucking action.

I am not able to identify if there is any generating action and if that action does exist, if it is assisting or opposing the output of the second coil. Obviously more work needs to be done.