PopularFX
Home Help Search Login Register
Welcome,Guest. Please login or register.
2024-11-26, 16:22:47
News: Check out the Benches; a place for people to moderate their own thread and document their builds and data.
If you would like your own Bench, please PM an Admin.
Most Benches are visible only to members.

Pages: 1 2 [3] 4 5
Author Topic: Pulse motor build off time.  (Read 60931 times)
Group: Guest
Hi All,

This is my update on the 2014 pulse motor build off.

https://www.youtube.com/watch?v=6h86yZ1g4qU

Tom O0
   
Hero Member
*****

Posts: 520
@Tommy Reed

Based on your last video, may I recommend you use your flyback charged capacitor bank to run a trickle charger that will charge the battery with the 12-14vdc it requires and not any more.

For efficient battery charging you need to stay within the battery voltage range and you can go as high as 20% of the battery amperage rating, (but at 20% that's not trickle charge anymore) and a minimum would be 3-5%.

That same trickle charger can charge a second bank of caps that could actually run the device if the battery is removed and enough energy is stored to keep it going. The last reason for a trickle charge is to make sure the battery does not receive high transients that could be flushed into your control circuitry. Flyback usually wants to generate a nice "spark" that your control circuits may not like on its feed battery.

The other point is this. Flywheels need a minimum rpm to start acting like a flywheel and that is to maintain momentum while a coil is at off position. Tesla would use lot's of armature in his motors when they were destined to be pulse driven to do the same thing. But the point is due to the mechanical limitations of the pistons, piston rods and center camwheel, I doubt you will be able to reach any rpm that the flywheel will be able to carry over as free rotation because each 45 degrees will be a pulsed piston, you have to make sure that the pulses occur right after maximum piston extension otherwise you may be pulsing the piston if it is before or at maximum and push it in deadlock or reverse which could be catastrophic for the mechanicals because there is always that flywheel looking to keep the same directed momentum of rotation. Very precarious situation. No room for error.

So actually the pulse to the piston will be dependent of how far past the maximum you need to be at the point where the piston rod is connected to the camwheel has to be at enough degrees past center since the piston will receive a zero to full maximum push thrust instantly and not the gradual push you produced with your finger pushing down on the piston. Two very different motive forces. There is no gradual in on/off pulsing.
 
The last caution is to make sure you never touch the outer edge of the flywheel while the system is turning since that is where you have the strongest back leverage where a pressure of 1 on the flywheel edge will transfer as a pressure of 10 (or 100) on the shaft and while those pistons are pulsing that could break the device.

So now I get your device but can't wait for this build off to end. Then I can maybe convince you to try putting a belt on the outer edge of the flywheel, run it with a small fast rpm DC motor that uses peanut juice to run and see how much raw juice you can produce off the piston coils without requiring any control circuitry. What I am most interested in is how much those coils can really output and not the other way around with all these fancy do dads, precision pulsing, counting degrees, redirecting flyback, all these are nice to make a good show, but for OU, all it needs is some help to rotate without anything else. The flywheel with a few magnets and one drive coil on a reed switch would have done it all having great leverage, low pulse energy consumption, simple design and see the output then. Just me as an OU hound dog sniffing things out. hehehe

Always a pleasure to see your videos, your enthusiasm is definitely contagious so I am just trying to check your back and anticipate any catastrophic actions, since we all know from past builds of all types, shit happens.

wattsup


---------------------------
   
Group: Guest
Hi All,

 There is no problem with my design, this is a update on testing BEMF.

https://www.youtube.com/watch?v=f0UZU5JU8v8

Tom
   
Group: Guest
Hi All,

Test run on the radial pulse motor..


https://www.youtube.com/watch?v=m3yFko2dI_M

Tom O0
   
Group: Guest
Test run on the radial pulse motor..

You da man Tom!

Question on the back EMF...   If you put an LDO voltage regulator, say an adjustable one and set it to, oh, 13.2 volts, can you pump that juice back into the battery to keep it charged?
   
Group: Guest
Hi Matt,

 I could try that, but first I must change my magnet wire to 24 gauge, 18 is pulling too much amps..

Tom
   
Group: Guest
Hi All,

Second test run, this time using a pwm to control speed.

https://www.youtube.com/watch?v=KwR6fkkr_w8

Tom
   
Group: Guest
Hi All,

I have put my videos on hold until Dec 14th and won't allow no more videos until this build off is finished.

I still have lots more to do, but If I plan to win I don't won't to show my complete finished radial engine yet.

I locked all video until Dec 14th.

Thanks and I hope you all understand.....

I'm in it to win guys O0

Tom
   

Group: Experimentalist
Hero Member
*****

Posts: 2982


Buy me a beer
 O0

regards

Mike 8)


---------------------------
"All truth passes through three stages. First, it is ridiculed, second it is violently opposed, and third, it is accepted as self-evident."
Arthur Schopenhauer, Philosopher, 1788-1860

As a general rule, the most successful person in life is the person that has the best information.
   
Group: Guest
Hi all,

Just for the day I will allow to show this second test run....

https://www.youtube.com/watch?v=KwR6fkkr_w8

Tom
   
Hero Member
*****

Posts: 520
@Tommy Reed

It is smart to keep your device closed at this stage of the competition. But we can still talk about theory here since there are enough videos showing the effect so far, results of which are perfectly expected.

So let's see..................

OK, about the flyback recovery. In the general sense, flyback is the spike produced after a primary or motor coil is disconnected from a feed supply or pulse. Notice I am saying "a" primary, meaning "one" primary and "one" disconnection.

But in your build, you have 8 primaries under successive disconnection and during those times of disconnection, only one of 8 primaries is ON while the others are OFF. But the major difference here is that while the primaries are being turned on and off, there is the continuous in/out movement of the piston magnets.

This means that while a primary is ON it is a drive coil, but while it is OFF, it is a generator and thus, is not only producing flyback at off but also actual generator style output. So in essence, the 8 pistons are always in a state of 1 drive, 7 generators.

So in this design you will never really have a singular flyback event. Each flyback event will be mixed with 7 generator events.

The heat or amperage draw of the coils is therefore not only dependent on the applied feed source but the actual energy dynamics of the drive coil becoming a generator when off and all the conflicting energy mixes. There is another factor at play here and that is the flyback diodes are only sourcing energy from one polarity hence wasting the other. You may consider using bridge rectifiers instead of those diodes to at least skim both polarities out of the coils. Since DC is additive by the actions occurring inside the coil, it also has to be subtractive when there are counter-conditions inside the coils, so bridge rectifiers may be a better solution there.

Another solution for this is rather simple. Eliminate the flyback.

The reasoning that the drive coils are using wire that is too thick and this explains the amps draw, is not completely right. Using thinner drive coil wire will only mean more turns in the same spool of wire, that will increase inductance inside the coils and create more flyback but will still react like a generator at off, with all the same counter-conditions so the problem is only shifted upwards now with more coil resistance.

If you are to keep this design, I would do the opposite of what you plan on doing and this is to find thicker wire and wind only one layer of drive coil of let's say 5-10 turns as the drive coil. Then the energy you used to fill those big drive coils would be sent to a few turns of drive coil wire where all the energy can now be fully concentrated nearest the piston magnet. Then test the motive action and if your flyback is rising. If there is very little flyback rise and your motive action is sufficient, that is good. Then if you want, you can always wind a secondary over the one layer drive coils and connect them to your flyback recovery that would now simply be secondary recovery because now, the few turns of primary drive coil will produce very little flyback and very little generator output, to then become the real drive coil it should be.

OK last point is drive coil positioning. The piston magnet has an inner polarity pointing towards the camwheel and an outer polarity pointing towards the piston opening. The drive coil should therefore not be positioned directly centered over the full piston stroke length. It should be positioned so that when the piston is receding back towards the camwheel, only one side of the drive coil having the same polarity as the outer magnet polarity will then influence with a strong repulsion only from that one side of the drive coil.  

The other option is to slide the drive coil down closer to the camwheel and use the outer polarity of the drive coil to attract the inner polarity of the piston magnet. If the wheel could work under coil-to-magnet as attraction mode, this would liberate the complete stroke length for you to wind a secondary coil over the normal stroke length. But if you ever do that, I would strongly recommend you consider the drawing I put up previously using multiple stacked coils instead of one coil. This will reduce the counter-conditions created by the magnet going in and out of the coil center.

Anyways, good luck man. I will be rooting for you, but remember, after the contest, you can do so much more with that build to push it to OU. hehehe

wattsup



---------------------------
   

Group: Experimentalist
Hero Member
*****

Posts: 2982


Buy me a beer
Now this is what I call a pulse motor >:-)

https://www.youtube.com/watch?v=xIDDSRJ_w8M
Some serious RPM here :D
regards

Mike 8)


---------------------------
"All truth passes through three stages. First, it is ridiculed, second it is violently opposed, and third, it is accepted as self-evident."
Arthur Schopenhauer, Philosopher, 1788-1860

As a general rule, the most successful person in life is the person that has the best information.
   
Group: Guest
Hi Cent..,

Put enough power into a motor and you can do just about anything, the sparks from the connection clearly shows a load with the transistor heat sink...

 Tom :-\
   
Group: Tech Wizard
Hero Member
*****

Posts: 1194
Hi Cent..,

Put enough power into a motor and you can do just about anything, the sparks from the connection clearly shows a load with the transistor heat sink...

 Tom :-\

Hi Tom,

I would like to understand what you exactly mean.

If you refer to the sparks shown at video time 2:26 and / or at 6:29 when he connects the battery clip to the supply pins of the board, then those sparks I believe come about due the empty electrolytic capacitor,  that cap charges up to 12 V.  Until he starts to spin the rotor by hand, the transistor switch is open and there is no any current going into the circuit after the electrolytic cap is fully charged but the rotor is still stationary.

Thanks,  Gyula
   
Group: Guest
Hi Gyula,

That is just my opinion, heat sink on the transistor tells a different story...

I believe he is pulling 12@5a what I read on the drawing. You won't produce that speed unless you're pumping more watts in that motor that would need a heat sink.

Tom
   
Group: Tech Wizard
Hero Member
*****

Posts: 1194
Hi Tom,

It is okay that the bipolar Darlington transistor type (TIP142) he mentions in the video is not listed among the better switching devices and the collector-emitter saturation voltage ranges between 1V to 1.5V or so, this definitely heats the transistorup when some amper current is switched.  I agree they are a waste to use in pulse motors if or when the highest efficiency is wanted.  MOSFETs are much better in this respect.
I mainly referred to the second half of your sentence where the sparks were mentioned, that is what I did not get. Still wondering how you meant any connection between the heat sink and the sparks.

Greetings,  Gyula
   

Group: Experimentalist
Hero Member
*****

Posts: 2982


Buy me a beer
What brought this video to my attention was he mentioned that there is next to no BEMF, and why the very high RPM. I would be interested to know why there is next to no BEMF!!

regards

Mike 8)

PS. this guy seems to know a lot about pulse motors, a seasoned builder up to huge machines.


---------------------------
"All truth passes through three stages. First, it is ridiculed, second it is violently opposed, and third, it is accepted as self-evident."
Arthur Schopenhauer, Philosopher, 1788-1860

As a general rule, the most successful person in life is the person that has the best information.
   
Group: Guest
I find the cut out the cancer mindset curious, sad, and at times, more often than not, humorous.  The majority view CEMF in a very negative light, I cannot comprehend the logic in this, but to each his own.  It's argued, an argument supported by observation that when the CEMF is limited, the consumption increases, and we end up with a stronger machine, a good thing under certain conditions, but as its well known, such machines must be governed mechanically, so....bad thing if the mechanical coupling breaks down.  In such a system if there is enough electrical energy doing mechanical work, failure in the mechanical coupling could lead to well....we all know what could happen.  

Why we even entertain the idea that we should reduce CEMF production is interesting to me.  To the machine the production of this force is as natural as breathing, something to think about, the breath of life was suggested elsewhere by another.  For those who would take that as a statement meant to appease to the religious at heart, it was not...  I'm also not in the business of converting folk as its also been suggested.

The question I pose to those who have spent any time contemplating this situation (To CEMF or Not To CEMF), wouldn't it make more sense to neutralize the effect (current limiting) that CEMF has on the system by finding and then applying an equal opposite force (CEMF)?  What greater or better suited force than CEMF itself could serve as this equal opposite......uh....CEMF?  If true then this would mean that it behooves us to establish the greatest possible number of oppositions to changes in current in such a system....wouldn't it?  The higher the system CEMF the greater the neutralizing power we wield over its current limiting ability....right?  

I find the idea interesting and feel support is given to such an idea when we remember that Tesla made the insane suggestion of adding choking coils, suggested that we "increase the circuits self induction, or in other words the circuits opposition to change in current, which means higher induced potentials (CEMF).  I maybe barking up the wrong tree, but I don't think so......my opinion, and it doesn't mount up to a hill o beans.....we shouldn't limit CEMF, we should establish those conditions which would...LET IT RIDE!


Regards
« Last Edit: 2014-12-05, 05:37:07 by Erfinder »
   

Group: Tinkerer
Hero Member
*****

Posts: 3055
Erfinder,

You've thought it out and have arrived at the
inescapable conclusion:  Things are the way
they are for a good purpose.

Well said!  Your reasoning is right on the mark.


---------------------------
For there is nothing hidden that will not be disclosed, and nothing concealed that will not be known or brought out into the open.
   
Group: Guest
Hi All,

I'm still working on my pulse radial engine, I want to win this pulse motor build off, so I'm adding goodies to the engine.

Tom O0
   
Group: Guest
Erfinder,

You've thought it out and have arrived at the
inescapable conclusion:  Things are the way
they are for a good purpose.

Well said!  Your reasoning is right on the mark.

I agree, I like to say "Back emf is our friend"  :).

Erfinder, said,
Quote
we shouldn't limit CEMF, we should establish those conditions which would...LET IT RIDE!

I take that to mean "Tune it to do what is desired".

..
   
Group: Guest
Erfinder,

You've thought it out and have arrived at the
inescapable conclusion:  Things are the way
they are for a good purpose.

Well said!  Your reasoning is right on the mark.

I hope my reasoning is on the mark.  My experiments lead me to believe that I am on the right track.  Thanks for the vote of confidence.


Regards
   
Group: Guest
I agree, I like to say "Back emf is our friend"  :).

Erfinder, said,
I take that to mean "Tune it to do what is desired".

..

What CEMF is exactly?  I've yet to cross paths with one possessing the qualifications to even offer an honest opinion.  Tons of good research has been going on over the years though.  The mechanism associated with the production of this force is well known and established.  The genius who coined the term "Inductance" whether known or unbeknownst to the individual at the time of penning the definition, reveals their supreme understanding and comprehension of the relation that this characteristic has to the generated force. Inductance is loosely (loosely equates to really simplified....) defined as being the opposition experienced when current in a conductor starts, stops or changes.  This definition should send chills down ones spine, and it usually does when you finally see whats being said. The funny thing about this is the author leads you to conclude that we are dealing with a characteristic, we know deep down that its anything but a characteristic.  We fight with ourselves and our peers, refusing to accept what could be considered as truth, because there is no precedent for the assumption, an assumption we won't even entertain.  So that I don't come across as a tease, I'll just state what we all should be considering.

Inductance = Magnetism

In light of this, parameter variation as its discussed in these circles needs overhauling.

Before those in the know went black, suggestions were begin made that all we need is to establish a difference in potential, for potentials move currents, those statements back then made no sense, what current?  They make perfect sense now, found the current.  Time passed as it generally does and folk stopped considering those statements, and the individuals making them moved on to simpler things, simpler demonstrations.

At any rate, CEMF is neither my friend nor my enemy, it is the soul of the apparatus, there to assist me in pinpointing the exact location, and the exact moment when change in the magnetic environs has taken place.  It's present whether I want it there or not, serving its purpose, a function which, when reading some posts, is beyond the comprehension of the majority.  

In my opinion, the machines as I have come to comprehend them are mechanisms through which counter electromotive force is magnified, magnified CEMF equates to magnified magnetism, whether you can put that magnetism to practical use is immaterial, the point is its presence.

As you didn't ask a  question, you simply made a statement, I offer the following.  Tuning is automatic, resonance is full spectrum.  To tune as your tone suggests, suggests limiting the system to the frequency the operator has determined will be the frequency of lowest possible impedance.  This is not what I am suggesting.  I am suggesting that Nature in its infinite wisdom has a mechanism which when comprehended, makes all frequencies "the" resonant frequency.  For this to function the circuit must behave as if it were both parallel and series resonant, both simultaneously and sequentially.  Tesla suggested this if not in word, then most certainly in deed, the works speak for themselves.


Regards
   
Sr. Member
****

Posts: 375
I will add my 5 cents :)

The CEMF term directly comes from Lenz law which basically express "for every action there is opposite reaction" and in mother Nature the opposite reaction is replaced by another opposite reaction of its own which redirects initial reaction to somewhere else then there is only action left to reach the balance... And that dual nature is in all over places.

Now if you think how we can mimic same behavior in induction, the CEMF is expressed by magnetic field of same polarity when the source magnetic field is trying to increase in strength on wire and it goes opposite to source when source magnetic field is weakening. On top of that in mechanical system we have kinetic force making this change and typically all generators and motors are using only 1 side of what mother Nature does so the fighting of kinetic forces of magnetic nature goes on over 100 years... All we need is to redirect Lenz force in middle of cycle so instead of single action there will be two actions in single cycle. Then you can control Lenz force in way you want as it won't be fighting against movement anymore.
   
Group: Tech Wizard
Hero Member
*****

Posts: 1194
What brought this video to my attention was he mentioned that there is next to no BEMF, and why the very high RPM. I would be interested to know why there is next to no BEMF!!

regards

Mike 8)

PS. this guy seems to know a lot about pulse motors, a seasoned builder up to huge machines.

Hi Mike,

On your question here is my 2 cents. First some further details on this pulse motor are included in an answer to mohammadreza in the comments under the video by the builder, Mister Caribbean Roots , I copied his answer here:

"Hi mohammadreza ramin,
Thanks for your comment and interest in my Pulse Motor. I don't have engineering drawings about it, i've just made some sketches by hand and went from there...that's how i always work...  I have 3 videos of this PM and they are on my channel...
Here are the links for the other two, https://www.youtube.com/watch?v=52le_92C2GE   https://www.youtube.com/watch?v=ecOjxyaa4e0
For images you can make some screen shots of the videos.
Here are some extra information;
Magnets are south/north configuration, Rotor was made on a lathe and it's solid aluminium with 12 holes for the magnets with each hole at 30 degree angle,
Magnets are 20mm diameter x 10mm height and are N42 Neodymium ones, The rotor is made like a flywheel with most of it's weight on the outer edge and this help with the energy storage properties which gives a lot of momentum which is the reason why it keeps spinning for a very long time when the input power is disconnected (gyroscopes works on the same principle)
The drive circuit here is very basic,  TIP142 darlington NPN transistor with a trigger coil, A diode from Emitter to Base,
A 400vac 0.1uf capacitor on the Collector and Emitter and this is to capture the b-emf (in my PM there is almost no b-emf), Theres a 1k resistor on the Base to the trigger coil. Trigger coil can be any coil but i prefer the higher resistance ones. this one here is a 59ohm one,
Run coil here is a very low ohm one, 0.6 or 0.9 ohm and it's a 1.2 or 1.8mm wire...can't remember which one it was...lol
The source capacitor is a 1000uf at 63vdc,  A small black heatsink on the transistor and that's about it...;-)
This should be enough for you to make a pretty complete information lecture about this PM setup...
Cheers"

So I think the claimed low or no BEMF may come from two things. One is he uses an air core coil for driving the rotor, this coil must have a relatively low self inductance by the look of it, its DC resistance is well under 1 Ohm due to the thick copper wire he mentions, so the number of turns is defined in the overall size for the coil. And a low inductance coil has a low BEMF 'property'.
The other reason for a possible low BEMF is that the rotor magnet poles are alternating as NSNS so this means I think the followings: when the coil is switched on, the magnetic pole of the coil's side facing the rotor magnets would attract one rotor magnet and at the same time would repel the neighboring rotor magnet (timing is important). And while the coil is on, the flux bridge existing in the idle or off state is broken between the attracted and the repelled magnets, and the moment the coils is switched off the neighbouring magnets flux return to their 'bridged' to each other state so that much less 'stray' flux exists in the vicinity of the coil than it would in case of a NNN or SSS magnet placement. So the induction in the coil by the approaching or leaving magnets is less in the off state I think.

I think this setup could be improved further on by splitting the single drive coil into several separate air core coils, and connecting these coils in series to switch them on and off at the same time. Lets say the drive coil now has 180 turns and we make 6 air core coils with 30 turns for each, from the same lenght of wire we used for the 180 turns single coil. All coils diameter should be identical
This way more flux from other rotor magnets (which are not used at all in the shown setup) could be used to interact with the input flux at the same time, using the same number of turns, and the torque and rpm would increase while using the same input power like for the single drive coil. Putting this otherwise: by activating the 'dormant' rotor magnets in this setup with more coils versus a single coil you can reduce input power to get the same torque and rpm a single drive coil produces as shown.

Mister Caribbean Roots (who built this setup) replaced the bipolar switching transistor with a MOSFET switch and also he replaced the trigger coil with a Hall sensor, the video links shown above include these changes.

Regards,  Gyula
   
Pages: 1 2 [3] 4 5
« previous next »


 

Home Help Search Login Register
Theme © PopularFX | Based on PFX Ideas! | Scripts from iScript4u 2024-11-26, 16:22:47