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Author Topic: Motor waveforms have OU and UU regions  (Read 5508 times)

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I am of the opinion that electric motors have Overunity and Underunity periods within their voltage and current waveforms.  If we load them only in the OU periods then maybe we can get OU motors.  The attached paper suggests how energy is taken from the atomic dipoles in the permanent magnet during those OU periods.  Any pulse motor enthusiasts out there?

Enjoy

Smudge
   
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It's turtles all the way down
Interesting paper and not not at all difficult  to build a simple switch to engage the load at the prescribed times.


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"Secrecy, secret societies and secret groups have always been repugnant to a free and open society"......John F Kennedy
   

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Buy me some coffee
Ok-im lost

@ Smudge
Your are talking about an electric motor with PM's,and the paper is talking about a generator with an electromagnet ???

In the paper,it says that the electromagnet is on permanently,and the generating coils are switched on at the required wave period (as far as i can work out). It would seem that is says to use only the power just before to just after the peak of the wave form. Lets say that the P/P voltage from the gen coils is 5 volt's-could we not just use a string of diodes so as they start to conduct say at 2 volt's,as each half of the wave form has a 2.5 volt peak. Why is there a need for the switching?

Brad


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Never let your schooling get in the way of your education.
   

Group: Professor
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Posts: 1859
Ok-im lost

@ Smudge
Your are talking about an electric motor with PM's,and the paper is talking about a generator with an electromagnet ???

In the paper,it says that the electromagnet is on permanently,and the generating coils are switched on at the required wave period (as far as i can work out). It would seem that is says to use only the power just before to just after the peak of the wave form. Lets say that the P/P voltage from the gen coils is 5 volt's-could we not just use a string of diodes so as they start to conduct say at 2 volt's,as each half of the wave form has a 2.5 volt peak. Why is there a need for the switching?

Brad

Ooops  :-[  You are right, my paper deals with a generator not a motor.  The electromagnet is just a gedanken experiment to illustrate that it (the electromagnet) would see alternating flux due to the magnetic field from the load current, and therefore the current source driving the electromagnet would alternately supply and receive energy.  Therefore in the PM generator the current sources in the PM (the atomic dipoles, orbital and spinning electrons) would also alternately supply and receive energy.  I can put up convincing arguments that this is the case.  What I cannot convince myself is that some of that quantum-derived energy can be captured in the load, maybe it just appears as magnetic field energy that comes and goes.  But if some can be captured then  clearly it can only be done during that part of the cycle when the atomic dipoles are supplying energy, so we would have to have the load switched in only during those time periods.  If the load was permanently connected the atomic dipoles would claw back the energy during the other part of the cycle.

Your suggestion of using a string of diodes to perform the load switching would work I think.

Smudge
   

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Buy me some coffee
Ooops  :-[  You are right, my paper deals with a generator not a motor.  The electromagnet is just a gedanken experiment to illustrate that it (the electromagnet) would see alternating flux due to the magnetic field from the load current, and therefore the current source driving the electromagnet would alternately supply and receive energy.  Therefore in the PM generator the current sources in the PM (the atomic dipoles, orbital and spinning electrons) would also alternately supply and receive energy.  I can put up convincing arguments that this is the case.  What I cannot convince myself is that some of that quantum-derived energy can be captured in the load, maybe it just appears as magnetic field energy that comes and goes.  But if some can be captured then  clearly it can only be done during that part of the cycle when the atomic dipoles are supplying energy, so we would have to have the load switched in only during those time periods.  If the load was permanently connected the atomic dipoles would claw back the energy during the other part of the cycle.

Your suggestion of using a string of diodes to perform the load switching would work I think.

Smudge
I actually think i have a setup already that may just show what your saying Smudge.I could never work out why it done what it did,but this may be the answer.I will have to go digging around in my storage shed to find it though,as i havnt touched it in about a year-and we have shifted house since then.

Infact,thinking of it some more,each electromagnetic pole segment on the rotor switches on at about 10* befor and switches off 10* after TDC of the generating coil.I can draw a current from 1 half of the wave form from the generating coil,and the rotor will bog down,but if i draw current from the other half of the generating coil's wave form,the rotor speeds up,and draws less current. I called this device the rotary transformer.



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Never let your schooling get in the way of your education.
   
Group: Elite
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It's turtles all the way down
The string of diodes will be very lossy. If these diode losses can be also tallied then it is ok.

 I prefer a more elegant method such as a transistor or mosfet  saturating switch (one for each half wave) whose turn on is triggered by either rotation angle using a cam or precise voltage level of the waveform.

I can work up a circuit for this if needed.

Also a reed switch properly placed and timing magnets on the shaft will also work, but will need careful adjustment. This could also have very low losses.

Edit: Now that I think about it a bit more, the diodes cannot work as they will conduct right through the peak of the waveform. According to Smudge, current must only flow at 45 thru 135 and 225 thru 315. No conduction allowed during remaining phase angles. Diodes alone will only provide a large crossover distortion around zero and 180 degrees of phase angle.

Smudge: How about using the excess energy to provide a push to the PM rotor at the appropriate time so no shaft input power required outside of a kick start? This would require storing the excess energy in a capacitor or inductor and releasing it to push the rotor during one of the available times when you are not extracting.
Or would this prevent the operation that you have proposed? Maybe something to try after the initial proposal shows signs of working.
« Last Edit: 2014-09-15, 14:48:24 by ION »


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"Secrecy, secret societies and secret groups have always been repugnant to a free and open society"......John F Kennedy
   
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